Hi,
yes, OTA upgrade worked fine. It 's a pan to find all information required to do an upgrade,… the manual doesn’t mention the upgrade procedure at all.
The most useful doc I found was included in the readme file of the release, hope it helps anyone else doing the update:
BTW: I did fine updating system-part1, then system-part2 and then (if both have been completed SUCCESSFULLY!!) the app itself. All that worked OTA, without beeing onsite at all.