Hallo Apple Engineers. Indeed I can confirm that 26.2 fixed the issue. But with BETA 26.3 the issue came back. My 100% Spritekit project that runs smooth with 60fps even on very old iphones (6s with ios 15 for example) - is now back stuttering , lagging at 40fps and less (iphone 13, ios 26.3) - Also todays BETA 26.3 (2) (23D5103d) - does not fix the issue - the issue remains. (It must be noted that the same app as of today runs with 60fps on an iphone 6s)