I dont know if this helps to understand the recent problems on that tablet better, but back in March or April I updated 3.2.x to 3.3, before the OBS updated some stuff.

After that I had two tablets running SFOS 3.3 with video output and bluetooth working. So it seems, there was a state of the repo, when at least 3.3 was working.

Right now, after I unluckily updated the tablets to 3.4 (I tested it on one and I thought after the first reboot video did work), I have to go back to 3.2 for video and bluetooth and the unability to use recent apps due to the ABI break or use 3.4 with the much better browser, up-tod-date api and no video and bluetooth working.