Unfortunately the French didn't make very good usage of the American aircraft that they did purchase in regards to putting them actively into service. As The Rise and Fall of the French Air Force notes:
Unfortunately, this prodigious American effort was not matched on the
French side of the Atlantic. La Chambre had estimated that it would take four
weeks to transport these planes across the Atlantic and assemble them.31
When the Neutrality Act was relaxed on 3 November 1939, the first batch of
Martin bombers was already ready to go but a shortage of Allied shipping
prevented the first leaving the United States until mid-December, when the
first batch of ninety-three Martin and eight Douglas bombers set sail for
France. By this time, it had rather belatedly been decided that it was better if
the planes were assembled in North Africa: the Atlantic crossing was safer,
the winter weather was better for training, and there was no risk of enemy
bombing interfering. The first American bombers arrived in North Africa on
Christmas Day 1939 and by the beginning of April, 215 Martins and seventyfive
Douglas bombers had arrived. Unfortunately, the facilities simply did not
exist to assemble the planes and more time was wasted while equipment and
personnel were brought over from France. A shortage of machine guns,
radios, and bomb racks caused further delays. The first Martin was not
officially accepted by the French Air Force until March 1940, seven months
after the Americans had handed the first plane over to the French authorities.
The first Douglas DB-7 was delivered to the Air Force the following
month.32
They had also ordered 6,000 engines which did not arrive from the Americans.
However, there are things which could change. The French had made plans to build the Rolls-Royce Meteor Engine, but relied heavily upon American industrial capacity for it. The declaration of war meant that under neutrality Ford pulled out his participation in the effort, which undercut it heavily. If that continues, then the French could be able to build more engines. Unfortunately I don't think that this would be that useful, since the French planned to use them in D.520, which were simply not available in sufficient numbers in May 1940. However, it could accelerate Amiot 350 production, as well as other tactical bombers, which would be useful.
One could see somewhat more aircraft, and perhaps somewhat better aircraft, but in the context of May 1940 it will not be enough. The only thing I could see changing is if the French are much more confident in their ability to pursue a long war, and hence alter around their strategy and planning. French Foreign and Defense policy 1918-1940 argues that by May 1940 the French were increasingly uncertain about whether their long term war strategy was working, and so were willing to look for increasingly risky secondary options to redress the situation, such as intervention in Scandinavia, bombing Baku, intervention in the Balkans, etc. If the French are more certain about their long term advantage against the Germans, with heavy backing by the US, then could neglect these secondary options to weaken Germany, not sending many new bombers and equipment to Syria, not providing the contingents for the Norway operation, not giving Weygand his forces for opening up a new Balkans front, etc. This might even trickle down to the French high command, where part of the rationale for the disastrous Breda variant of the Dyle strategy was to save the Dutch forces, needed to redress the balance of power against the Germans when the total German strength was very much-overestimated.
How likely is this? Not very likely at all I fear, as i'm unsure that the French would draw this lesson, and even if they did, that they would appropriately utilize their resources. But the possibility exists, albeit a low percentage.
Much more likely however is that this sign of American assistance for the Allies on such a scale means that the French fight on from their Empire, but France has still fallen so that is a different question.