I think that if we can show the OTL belligerents are a push, Germany having some hot but still buggy new high tech stuff but in small numbers, Britain and France have relatively backward kit but in very large numbers, and don't forget that time bought by the OTL delay favored not only German technology shaking down but also the training and seasoning, as much as possible in quasi-peacetime (but don't forget here the exercise green Germans got in locking down former Czechoslovakia), then when we factor in that Hitler has not already conquered Czechoslovakia, we have to favor the Allies overall.
Doubly--as observed above, Hitler does not possess Czech munitions works and has not had a year to work them and appropriate pre-Munich accord stocks on hand.
And forgotten by all--Czechoslovakia can fight. It seems to be assumed this will be a brave but pathetic show, but the Central European federal republic had some real assets on its side, including the defensible Sudetenland frontier. Yes, that might be somewhat subverted by Sudenten-German treason, but I think in the crisis the Czech security apparatus will be at least somewhat prepared to take countermeasures, enough that while there might be some unfortunate easy penetrations of the fortified frontier here or there, on the whole the border will hold and the few German early breakthroughs due to fifth columnist German citizens of CZ will be limited and dealt with by CZ reserves. There is also the question of whether Slovaks would prove treacherous too, but I think that in the situation that at least France honors the long time defensive alliance instead of chickening out as OTL, Czecho-Slovak morale will be high and they will fight near the peak of their potential. They know what Hitler is like, they are fighting for their Slavic lives!
If they think France will honor her commitment and strike at Germany's southwest border, either the French punch through and overrun south Germany and discredit Hitler that way, or he has to deploy a lot of what force he has to try to parry them there.
Furthermore the OP seems to take as given that the less formally committed British also get off the fence and back Czechoslovakia and France; again there is little Britain can do to directly relieve the Czecho-Slovaks but a lot they can do to shut down German commerce.
Other countervailing soft factors to the view that the war is equivalent to waiting year include that in this ATL, Britain and France have not used not only the assurances France made previously to Czechoslovakia as toilet paper, but also the League of Nations as well...with Germany acting in a plainly rouge fashion, and the two most dominant nations in the League united in DOW on Germany I think there is a real chance the League might show some real backbone as a collective security agency. The revived Entente will want the legitimization of acting in a peace-keeping League mandate, and the momentum might not be sufficient to get Netherlands, Belgium and who knows maybe even Denmark to declare actual war, still these nations (maybe not vulnerable Denmark..but then again, when ever will the Danes have a better chance to catch Hitler with his pants down?) might at least in compliance with League resolutions become very unfriendly neutrals, mobilizing their armies and not inconsiderable navies, sealing their borders against all trade or travel, and the noose of strategic isolation closes tight around the Reich.
By this late date, Mussolini was beginning to come around to Hitler's side but that relationship has a year less to mature; might he be waved off and close his border with former Austria too? Perhaps in consideration of crass concessions such as a freer, League approved hand in Ethiopia? Maybe even a reluctant but resigned League green light for his desired Albanian imperialism?
Can Poland be asked, if not to actually declare war on behalf of the League which is now an Anglo-French sock puppet, to like the Lowland kingdoms mobilize and close the borders, and perhaps be so bold as to be the League's agent in securing the League Mandate "free city" of Danzig, which had a strongly pro-Reich population to be sure.
Might League auspices lubricate the passage of RN battle groups through the Danish straits to harry north German shores? Perhaps this is where the RN learns a costly lesson about German airpower but unless the Germans want to trigger Danish involvement they can't bomb RN units in inner Danish waters, so the RN foray could at least retreat to probable safety there, and if Hitler violates Denmark then they can assist Danish forces while Britain and France send more help to reinforce and strike at Germany from yet another direction. German force collapse seems more a matter of "when" than "if" to me!
Now vice versa the Entente probably does not have the stomach to invade Germany wholesale and be forced to unconditional surrender; Hitler can probably talk his way out of being deposed, but I think one term would be to disgorge any conquests in Czechoslovakia, and just maybe perhaps to detach Austria as well.
Obviously then I am on Team Hitler-Gets-Pwned, but one thing I was never on board with in that fusty consensus was, the certainty so many had that Hitler therefore goes down. On one hand his credibility, as either a trustworthy negotiator or a conquering genius, is shot to hell and stomped on. On the other as OP observed he was a wily and uncannily lucky snake, remarkably hard to shake off. His domestic credibility with the upper classes is shot, but by 1938 I suppose the Party is blindly loyal already and he has enough SS and SA remnants, plus the tendency of Gestapo cops to prefer him and his blessing of what they called "positive justice" that barring some swift and coordinated and unlike OTL actually successful Valkyrie operation the Generals were never near capable of pulling off OTL, which the consensus OP protests just assumes happens as a matter of course, he remains Leader until some invaders come and pry the title out of his stiff cold hands. So it is entirely possible this whole war covers the Entente and League in rose colored glory and yet several years later Hitler strikes and conquers.
A note on allegedly obsolete aircraft by the way...Biplane does not mean useless. In this year the overwhelming majority of the Luftwaffe has typical mid-30s biplanes with streamlined bodies too. So does Britain with the Gladiator, though the Hurricane is just around the corner. Czechslovkia's Avia made some of the very best of these types and OTL the Reich deployed them in loads of secondary fronts. Perhaps the Messerschmitts might have eaten these for lunch--but as noted, the good Me-119s are still down the road a bit. Anyway the Allies have loads of these biplanes. The Republican/Loyalist side of the Spanish Civil War used largely Soviet built fighters--and IIRC, the monoplane version was superseded by a better biplane which contended with the vaunted Condor legion quite well.
Man do I miss Just Leo, he could have straightened all this out.
The point being, don't dismiss the aircraft Britain and even France had in '38 or assume they are made of candy. Many a Condor Legionaire regretted that assumption I am sure.
Doubly--as observed above, Hitler does not possess Czech munitions works and has not had a year to work them and appropriate pre-Munich accord stocks on hand.
And forgotten by all--Czechoslovakia can fight. It seems to be assumed this will be a brave but pathetic show, but the Central European federal republic had some real assets on its side, including the defensible Sudetenland frontier. Yes, that might be somewhat subverted by Sudenten-German treason, but I think in the crisis the Czech security apparatus will be at least somewhat prepared to take countermeasures, enough that while there might be some unfortunate easy penetrations of the fortified frontier here or there, on the whole the border will hold and the few German early breakthroughs due to fifth columnist German citizens of CZ will be limited and dealt with by CZ reserves. There is also the question of whether Slovaks would prove treacherous too, but I think that in the situation that at least France honors the long time defensive alliance instead of chickening out as OTL, Czecho-Slovak morale will be high and they will fight near the peak of their potential. They know what Hitler is like, they are fighting for their Slavic lives!
If they think France will honor her commitment and strike at Germany's southwest border, either the French punch through and overrun south Germany and discredit Hitler that way, or he has to deploy a lot of what force he has to try to parry them there.
Furthermore the OP seems to take as given that the less formally committed British also get off the fence and back Czechoslovakia and France; again there is little Britain can do to directly relieve the Czecho-Slovaks but a lot they can do to shut down German commerce.
Other countervailing soft factors to the view that the war is equivalent to waiting year include that in this ATL, Britain and France have not used not only the assurances France made previously to Czechoslovakia as toilet paper, but also the League of Nations as well...with Germany acting in a plainly rouge fashion, and the two most dominant nations in the League united in DOW on Germany I think there is a real chance the League might show some real backbone as a collective security agency. The revived Entente will want the legitimization of acting in a peace-keeping League mandate, and the momentum might not be sufficient to get Netherlands, Belgium and who knows maybe even Denmark to declare actual war, still these nations (maybe not vulnerable Denmark..but then again, when ever will the Danes have a better chance to catch Hitler with his pants down?) might at least in compliance with League resolutions become very unfriendly neutrals, mobilizing their armies and not inconsiderable navies, sealing their borders against all trade or travel, and the noose of strategic isolation closes tight around the Reich.
By this late date, Mussolini was beginning to come around to Hitler's side but that relationship has a year less to mature; might he be waved off and close his border with former Austria too? Perhaps in consideration of crass concessions such as a freer, League approved hand in Ethiopia? Maybe even a reluctant but resigned League green light for his desired Albanian imperialism?
Can Poland be asked, if not to actually declare war on behalf of the League which is now an Anglo-French sock puppet, to like the Lowland kingdoms mobilize and close the borders, and perhaps be so bold as to be the League's agent in securing the League Mandate "free city" of Danzig, which had a strongly pro-Reich population to be sure.
Might League auspices lubricate the passage of RN battle groups through the Danish straits to harry north German shores? Perhaps this is where the RN learns a costly lesson about German airpower but unless the Germans want to trigger Danish involvement they can't bomb RN units in inner Danish waters, so the RN foray could at least retreat to probable safety there, and if Hitler violates Denmark then they can assist Danish forces while Britain and France send more help to reinforce and strike at Germany from yet another direction. German force collapse seems more a matter of "when" than "if" to me!
Now vice versa the Entente probably does not have the stomach to invade Germany wholesale and be forced to unconditional surrender; Hitler can probably talk his way out of being deposed, but I think one term would be to disgorge any conquests in Czechoslovakia, and just maybe perhaps to detach Austria as well.
Obviously then I am on Team Hitler-Gets-Pwned, but one thing I was never on board with in that fusty consensus was, the certainty so many had that Hitler therefore goes down. On one hand his credibility, as either a trustworthy negotiator or a conquering genius, is shot to hell and stomped on. On the other as OP observed he was a wily and uncannily lucky snake, remarkably hard to shake off. His domestic credibility with the upper classes is shot, but by 1938 I suppose the Party is blindly loyal already and he has enough SS and SA remnants, plus the tendency of Gestapo cops to prefer him and his blessing of what they called "positive justice" that barring some swift and coordinated and unlike OTL actually successful Valkyrie operation the Generals were never near capable of pulling off OTL, which the consensus OP protests just assumes happens as a matter of course, he remains Leader until some invaders come and pry the title out of his stiff cold hands. So it is entirely possible this whole war covers the Entente and League in rose colored glory and yet several years later Hitler strikes and conquers.
A note on allegedly obsolete aircraft by the way...Biplane does not mean useless. In this year the overwhelming majority of the Luftwaffe has typical mid-30s biplanes with streamlined bodies too. So does Britain with the Gladiator, though the Hurricane is just around the corner. Czechslovkia's Avia made some of the very best of these types and OTL the Reich deployed them in loads of secondary fronts. Perhaps the Messerschmitts might have eaten these for lunch--but as noted, the good Me-119s are still down the road a bit. Anyway the Allies have loads of these biplanes. The Republican/Loyalist side of the Spanish Civil War used largely Soviet built fighters--and IIRC, the monoplane version was superseded by a better biplane which contended with the vaunted Condor legion quite well.
Man do I miss Just Leo, he could have straightened all this out.
The point being, don't dismiss the aircraft Britain and even France had in '38 or assume they are made of candy. Many a Condor Legionaire regretted that assumption I am sure.