Things are evolving on this front: we are now at 275 hours per year instead of 250 to compensate for the Rafales sold second-hand and it is possible that we will go up to 300 and more to stay within a 30-year life span. In fact it is thought that after 30 years it is not very interesting to extend an airframe, in fact it is this data combined with the 7500 h life achievable that has led to the figure of 250 h per year which combined with the operational contract has itself led to the volume of Rafale needed.
The increased flying time shouldn't affect the Rafale M though. The Ms are the oldest after all. 2 jets in the year 2000+36 = 2036.
And AAE's missing jets will be replaced within a few years anyway. So even the extra 25 hours is over a very short duration. 250 hours for most of its life, 275 hours for 4 years, it's not much, just 100 hours extra. It will still mean AAE's oldest jets will need replacement from 2040 instead of 2041, 'cause IIRC 2005 is when they got their first jet, which is still going to be peanuts.
To sustain a line without exports after, say, 2033, Dassault will need 77 jets. I don't believe that many jets will require replacement.
So, what, MN will need 2 or 3 jets starting from 2036 and AAE will need a little less than half a squadron in 2040.
MN's fleet will also be problematic, with half of them new built Rafales and the other half NGFs.
I am also more inclined to believe that as the jets get older, the training requirements will reduce and flying time will decrease in exchange for greater lifespan. Possibly 21 hours a month to 15 hours, ie 180 hours a year. So the replacement period can get stretched even more. After 31 years at 250 per year, 180 hours will add 2 more years. So, instead of 36 years, you can get 38.
So the French active duty fleet needs an expansion from 225 to the original 286 or beyond in order to sustain the line. The 2030s production can't replace older Rafales. And with pretty much all of the production going to AAE. If FCAS goes ahead, MN will have to wait or get stuck with two types of jets at the same time.
But if FCAS is cancelled, then AAE/MN will have to start replacing their jets very prematurely, as much as 2034, in order to sustain the line.