You have all been so helpful in my quest so here is the update 
I've ordered the same Ted Baker dress in a smaller size to see if that solves the issue (I'm collecting it on Monday)
I've got 5 other dresses (as highlighted here) either ordered or on hold in stores which I will get by midweek.
A decision will be made by Friday.
No more suggestions please as I really don't like clothes shopping and I have put more effort into this dress search than ever before and I'm over it now. 
Fingers crossed the eventual dress doesn't get the Covid curse!!!