But how do I find out the exact execution time?
This is an issue if you didn't actually monitored it with a live counter
since the timestamp used in the blocks where you can base the time isn't always accurate.
If possible inside Electrum.
The timestamp that you see in the 'History' tab is actually the updated timestamp based from the block where the transaction is included.
Electrum doesn't include a date/time when you send a transaction and it got listed in your History tab as "
Unconfirmed", the time is only until its confirmed.
So either set a timer to get an accurate stats or rely on the timestamp which is based from "
median timestamp".
Explained here:
en.bitcoin.it/wiki/Block_timestamp