I  have upgraded from engine and after reboot the engine knows that I have no more updates pending.
This is my flow:
0.Engine upgrade
1. Host is moved in maintenance (from UI) - no ticks for stopping gluster. Automatically evacuates  all VMs.
2. Use UI to check for updates
3. Update host (keep tick for autoreboot)
4. Wait for hostto come up and general system & gluster healthcheck

Best Regards,
Strahil Nikolov