That's the problem with large paragraphs and inconsistent ways of showing the time. Difficult to follow.
Off at 14:00
On shortly after 14:00
Off again at 21:00
Assumed on again shortly after 21:00
Off at 07:10
On again 17:55
Off at unknown time
On again 19:00
Off at 19:35
On again 19:45
Think it's off again at 20:05 and every 10 to 20 minutes until ... 21:00 ?
So it stayed on for 7 hours in the afternoon, then overnight for 10 hours, then for an unknown time during the day, and then when you were there in the evening the trips were was much more frequent.
Well it sounds like something that isn't used overnight but while you are there. It could be the heating / water. You might try switching it off for a day and using a small heater and kettle, see if the problem goes away.
Or, while you are home, there are lights and TV and radio and cooker etc on that isn't used overnight. But the fact it did trip during the day suggest to me it isn't likely to be something you plug in while you are there.
I think it's a case of gradually eliminating the potential sources of the problem.
Is it a fridge/freezer causing a power spike maybe ? Difficult to switch off your freezer for too long, but it may pay you to take it off for a while (just don't open the door). But again, why not at night if it's that ?
Can only suggest removing stuff in sequence and seeing if the problem goes with any particular load.