Hi,
From the log, it appears that there are two issues when migrating using the direct site-to-site method.
The first is that the connection between the two sites is quite slow, so each file is taking far longer than expected to upload.
The second issue appears to be an unusual interaction between how long the task is allowed to run at once by the server and UpdraftPlus’ resumption system (and how it prevents overlapping runs). This is causing the time between resumptions to become very long.
I will forward this issue on to our developers.
In the meantime, you may wish to use one of the alternative transfer methods when migrating. These can be found in Step 3 of the following guide:
https://updraftplus.com/faqs/how-do-i-migrate-to-a-new-site-location/
Best Wishes,
David N