Glad to hear things are back to normal.
For what it's worth, VM say that on M250 you should see average download speed of 264Mbps and average upload of 25Mbps.
I'm on M250 and right now the samknows.com speed test shows I'm getting 271 and 27.1
In all honesty, if your VM email account is only 25% full I would not have expected that to be an issue so personally I would not stress too much about deleting lots more emails 😉
It is also worth saying that when you set up an IMAP account in an email app or client it can take a while to synch the first time that you run it but it then settles down after that.
Anyway, I'm glad it seems to be ok at the moment. If you do see the synch process hanging again it might be worth running the speedtest again just to see if you have an intermittent issue with your broadband.
If in the future you do see the speed drop significantly there is a board on this forum dedicated to those specific issues. https://community.virginmedia.com/t5/Speed/bd-p/Speed so you could create a post with the details there. The experienced forum members there will be best placed to help you with any problems in that department.
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