I was doing some new dev today on 4631 based system.
I noticed there was a new 0.4.4 bootloader from 4 months ago.
I decide to update the module i was working with.
After the update, all seemed normal in my project code.
And UF2 flashing worked.
When i tried BLE DFU it connected but failed to initialize using my iphone.
I checked doing same from my Andriod tablet, it to failed to initialize also.
I switched the bootloader back to 0.4.2
Both iphone and andriod ble dfu worked as it always has in our projects.