How to ensure a hawkbit update is confirmed before triggering a reboot

[BubuOT]

Recently I've been looking at a strange problem where sometimes rauc-hawkbit-updater doesn't confirm actions to hawkbit before we reboot the system (there's a custom service listening to rauc's 'Completed' dbus signals, then decides whether to reboot the system or not, but it always waits for 5s after getting the signal).

But apparently this 5s wait is sometimes not enough for rauc-hawkbit-updater to process the completed message itself and send the update confirmation status to hawkbit? (the end result is that the update is reapplied after the reboot and then it just does that in a loop eternally)
So, this somehow seems to occur when the update is very fast (because due to adaptive updates it doesn't actually need to download much).

Is there any reason why rauc-hawkbit-updater would not process the completed message fast enough (within 5s)? The only thing that would currently make sense to explain what we are seeing is that it somehow doesn't process more than x dbus messages per s, so when the whole pdate basically completes within a few seconds it can't keep up fast enough?
But now sure why that would be the case. (maybe rauc-hawkbit-updater might be waiting on all the status messages to be successfully send to hawkbit before processing the install completed message?)

Any other ideas on how to wait for rauc-hawkbit-updater (without just arbitrarily setting the reboot timer to 30s or something) to have finished reporting the update state?

Would it make sense for rauc-hawkbit-updater to send out a completed dbus signal we could listen to instead of relying on the one from rauc + an arbitary delay?

[BubuOT]

I just saw #172 which might be an alternative solution to this. (confirm the installation manually after reboot and only start rauc-hawkbit-updater afterwards).