Vodafone had a more experienced support rep phone today at 1pm and he went over some things.
He was able to test on his PC and could see some of the problems but not all of them
Eventually, he suggested trying on Fire Fox which was fast (just like I am used to) immediately with no problems at all.
In teory then it was all about some issue with Explorer.
There is no evidence that it wasnt partly an issue with Vodafone as well, as I had changed nothing on Explorer over the weekend.
But the issue is resolved in so far that I can do my work.
Fingers crossed no other customers have this problem.
Thanks for feedback from all