My 21 is on the latest sync version and APIM update sync 25094. There's a thread out there with information that some 2021s that are on sync versions from 2022 and older currently won't get new updates until Ford releases them to those trucks.
My most recent update was ECG-24.2.5.6.1 way back in September. I just got SYNC-25.2.1.6.5 this afternoon. I never saw any of the other updates in between those two. In fact, I was still seeing phantom messages for the ECG update almost weekly.