This is inconclusive, but yourself and Jon are both using Plusnet to receive your email notifications and both are delayed, and I'm not using Plusnet and mine aren't. It sounds to me like something Plusnet are doing, possibly busy mail / anti-spam server, rather than something this server is doing.
I'd try changing email address registered here to see if that improves things. Or go to Plusnet and ask them why they're delaying the email notifications.
I had also decided that the issue was with plusnet and that I could live with it since I don't really use the emails anyway (just come every day(yj))
I have recently notived that other mail is being delayed by plusnet though, so I'm about to ask why
Just in case you're unaware: you can disable the email notifications, if you don't want them.
My Controls > Emails & Privacy.
Fourth checkbox from top.
I did know, but thanks anyway
I'm going to use the timings etc to ask plusnet questions
Ha! When I looked the box was checked, but then I realised that the email address is fictitious. Although there may well be some poor bastard @hotmale.com who's getting a lot of confusing email notifications! :$