My average FPS decreased about 1/3 due to the update. At cruise altitude, FPS was about 45 FPS, now is around 30 FPS. Near smaller airports (non-photogrammetry) FPS was upper 30s to low 40s, now at 25-30. The patch causes much more trees to be rendered, but lowering LOD or tree settings does not help much in the FPS department.
CPU load became a major bottleneck again. The average GPU load went down with the FPS (RTX 3090, 4K Ultra Settings with some customizations). Micro stutters and multi-second freezes are still there. I am seeing a total of about 10 to 20 seconds of multi-second freezes per flight hour.
What I am also seeing is a slow but steady decrease of FPS the longer the sim runs. I perfomed a flight with the TBM 930 from a small German airport to a small regional one in the alps (about 70 minutes flight time). FPS averaged at low 30s. I performed the same flight in the opposite direction. Average FPS was high 20s. Flew the same trip back to the alps (same conditions). Take off was with low 20s, gradually went down to 15 while in cruise. Landed at about 10 FPS. After landing, FPS returned to high 20s. The sim was running for about 4 hours at this point.
Yesterday, shortly after the update, I had to abort a flight in a photogrammetry area because the same FPS decrease happened within 25 minutes after takeoff. When the FPS gets below 10, memory consumption increases 10-30 MB per second until RAM is full. Apparently, the sim does not manage to release memory fast enough if FPS is too low.
I first noticed this progressive FPS decrease with the March update. I did not manage to reproduce it reliably, but it got a lot better with the hotfix, allowing 5 hour flights with only a marginal FPS drop. Now it is back, but worse.