Lloyd understandably didn't want another meat grind, however Haig was a conservative darling whose removal would threaten British unity, so he withheld troops
That is the traditional interpretation. From what I can tell the situation is actually a lot more complicated. The War Office apparently doctored their figures when giving them to Cabinet. Presumably they were aiming to force the government to allow expanded recruitment, including from industry (As much as I like Willy Robertson, he tended to see politicians as an obstacle to be neutralized rather than political masters, so I can kind of believe this). The Government therefore had no trust in the numbers being given to it, and little trust in their military advisors.
Nevertheless, it appears that the government did actually try to find more replacements, as they were the ones who suggested drawing down the Home Army and reducing the requirements for frontline service. The War Office refused.
I am not a big fan of Lloyd-George, and I think he certainly contributed to the problem with commitments to Italy and other fronts and extensions of the British line that the BEF could not really afford. He also almost certainly lied to Parliament about the manpower issues. But it is not completely clear, to me at least, that he was responsible for holding back reserves artificially. Relations between the government (particularly Lloyd-George) and the War Office during WW1 make for a frustrating and dysfunctional tale.
Considering thos dumps were primed to blow when the Germans got nere them, it dosnt seem like they were evacuated (not to mention mostly impossible, there was way to much ammunition to be moved in that short amount of time)
I rechecked Zabecki, since I had it open and he said this on page 289:
The British, meanwhile, had already cleared their ordinance depot at Amiens, and were developing plans to blow up the ammunition dumps on their southern line of communications.
He references Ian Malcolm Brown's "British Logistics of the Western Front, 1914-1918" for this one. Since that is a $160 book and the preview does not cover page 186, I will have to take his word for it.
Couple things with this. For starters, I misremembered the date. This was on the 28th March, not the 25th. Second, we were both partially correct. The Depot at Amiens was cleared but by the 28th, not the 25th. The British were looking at blowing up their ammo dumps along their southern line. This would probably be the one running along the south side of the Somme in the following Map:
If so, that does not mean that they were blowing them immediately. Just that they had plans to do so. They would likely blow them if and when they came under threat of capture by the Germans.
Alternatively the "southern line of communications" could technically mean the lines running south and west of Amiens that had been supplying Fifth Army. However, these had been taken over by the French on the 25th at the same time as Fifth Army had been put under French command, so the first interpretation seems more likely to me.
You also note from this map that, if needed, the British can use Abbeville and Doulons to transfer supplies for an assault to retake Amiens. They are not as good as Amiens but they would work for the time being.
the plan really was to evacuate past the somme if Amiens was captured, including most of the British army back to Britain,
Zabecki says this in his section on March 25th( page 257):
The British Q-Staff also prepared to fall back to the north, and started to develop Scheme X and then Scheme Y to increase the supply flow through the northern ports, while shutting down the southern line of communications.
And this on page 572:
Around 25th March Q-Staff started developing contingency plans (Scheme X and Y) based on having to abandon their northern line of communications. Then they developed Scheme Z to abandon the southern ports and lines of communications.
To get some more detail I checked Zabecki's source list. In both cases he references A.M Henniker's "Transportation on the Western Front 1914-1918". Thankfully, this volume is archived online (
https://babel.hathitrust.org/cgi/pt?id=uc1.$b633844&view=1up&seq=457&skin=2021).So I took a look at the section mentioned (page 402-411).
Here is what it had to say on Scheme X and Y:
As early as March 26th the advance of the enemy towards Amiens led to a meeting under the Q.M.G to consider the arrangements to be made to meet the contingency of the enemy pushing a wedge between the British and French, with the consequent loss of the southern L .of C. At this meeting it was arranged that certain movements should be started at once. On March 31st the C.G.S communicated to the G.O.C L. of C a "Scheme X" for the disposal of personnel, animals and stores from the Amiens-Abbeville-Blargies-Dieppe area. Later the scheme developed into "Scheme Y" with accompanying evacuation schemes for (a) Calais and Dunkerque, and (b) the Abbeville, Abancourt and Dieppe areas.
So Scheme X was just a shift of resources off of the line that terminated in Amiens. This was likely in response to the possible loss of Amiens. Only Scheme Y includes evacuations, and could be the source of the evacuation from the continent assumption? Its not entirely clear. A trigger condition is not shown in regards to this plan. Its also not clear when it evolved from Scheme X. It would have had to have been sometime in Early April as Scheme Z only came about on March 31st and the policy decisions that drove Scheme Z came about in April.
As to Scheme Z there is actually a lot to unpack here:
Page 384
Pending the arrival of American forces in sufficient strength to enable to offensive to be assumed the strategic aims of the Allies were threefold. The primary aim was to prevent the enemy separating the British and French forces and then overwhelming each in turn; the second aim was to cover Paris; and the third to cover the Channel Ports. A serious advance by the enemy between Arras and the Somme would isolate the British from the French; continuous fighting with heavy losses on any part of the front might make a drastic reduction in the length of the front held by the British inevitable. In the event of either of these possibilities, to secure the first strategical object of a continuous front it might be necessary to abandon the entire area north of the Somme.
The British aims were to cover the Channel ports while at the same time keeping in close touch with the French on the British right; the avowed intention was to maintain all ground held and make no voluntary withdrawal; the GHQ defence line was being constructed and preparations made for the inundations as a precaution and for emergency use only. But at the same time in view of the possible eventualities, a scheme known as the Z scheme was being worked out for the complete evacuation of the whole area north of the Somme and for a new line of defence along that river.
Page 402 (following on from the Scheme X and Y info above)
During April the policy was adopted of maintaining a continuous front even at the expense if necessary of abandoning the whole area north of the Somme; the scheme for such a retirement was known as the Z scheme.
So, a couple things come to light from this:
1. Perhaps most glaringly, Scheme Z was
not a withdrawal across the Channel to Britain. It was actually a withdrawal south to the Somme. Perhaps others here caught on to that earlier but I did not. This means that if Scheme Z was implemented, then the British and the French would still be operating alongside each other on the continent. Therefore, if Scheme Z were implemented, the stated aim of the Spring Offensives (to knock the British out of the fight before moving on to the French) would not be achieved.
2. The British were not hovering over the button to implement this plan. This was an emergency plan only.
Further reading of the section that Zabecki quotes reveals some other tidbits:
1. It was not finalized and ready for implementation until July. This was not a plan that GHQ had on hand to implement if things went wrong in the spring. It seems more like because of the Spring Offensives Scheme Z was planned as a "just in case this happens again" type of thing.
2. It's planning was the province primarily of the Director of Transport, not the Quartermaster General.
3. Stores were the lowest priority item considered for evacuation. This makes some level of sense. The stores in the logistics system in France do not constitute long term storage, but a pipeline to the front, with its cargo being often used as fast as it is shipped across the channel. Destroying it is not ideal but does not represent a catastrophe as long as more can be brought from the source. The important bits were the support infrastructure that had been set up over the last 3.5 years. And it looks like most of this was accounted for in the move.
4. Trigger conditions mention Amiens but not Hazebrouck. At least according to this source British were obviously worried about Michael and the threat to Amiens, but more because it made it harder to stay in contact with the French than because of the loss of Amiens. Likewise, the section on Scheme Z does not greatly mention Hazebrouck but the worry that an advance in Flanders would allow the Germans to cut off or slow down the transit from some of the Northern ports (hence the mention of the GHQ line).
So it seems that at one point the evacuation of the BEF, possibly to Britain may have been considered in Scheme Y. At some point in April the decision was made that any retreat would be to the south to remain in contact with the French. It is hard to say how that would have gone but that was the plan. In every case, these were contingency plans. They never reached implementation and it is not guaranteed that they would be. They were prepared by the Director of Transport, under the authority of the Q.M.G, not directly that of GHQ, the C-in-C or the War Cabinet.
To my mind, even if, in that brief period that Scheme Y was the dominant plan, the British felt the need to implement it, Political needs would cause Whitehall to stop a full evacuation of the BEF from the continent, assuming that is what Scheme Y is actually suggesting.