had the same on sram dub x1 carbon cranks, initial install, so fresh with no grit and a bit of grease, torqued up (as my previous sram dub descendant carbon cranks) and forgot to do something so had to immediately take them off, and stuck, was absolutely impossible to budge, hammer came out, dad holding bike and just about got it budged, made a awful sound when releasing!
so super lubed it back up next time, and its been easy to get off since like the descendant dubs were…no idea what causes it tbh
as for the BB ive actually had real good miles and horrid winter conditions for the price, still smooths nicely, the stupid little blue seals are a awful design though as they literally fall out of place on removal and installation!
better than the piece of shit hope one it replaced anyways!