@arubislander Yes I have installed Dekko 2 but I habitually close all apps before going into standby. Would it be worth uninstalling Dekko (tomorrow) and seeing if the problem persists?
No need for such drastic measures. What you could do though is open the Terminal app and after typing
$ stop ubuntu-push-client
That should stop Dekko from checking for notifications until you reboot the device.
Alternatively, you could disable all notifications for the Dekko app in the System Settings and see if that helps.
I tried both of those measures one at a time but no difference; tablet still wakes up intermittently.
This bug is already reported: https://github.com/ubports/ubuntu-touch/issues/291
There is another report linking it to the sync of the contacts and calendar, but I'm not able to find that one right now...
The bug report indicated that turning off wifi would stop this behaviour and it does, which is useful. I tried turning off notifications for calendar for a while but that made no difference.