Why is xara continuing to publish 'old' files even tho i've exported newer ones?

For the sake of other users, can you explain how you got it sorted? Thanks.

You were right, it was all to do with publishing the files to the correct folders in my webspace at 1and1 - we seemed to get at the right combination by trial and error but now it works.
In case it helps others my process is: export to folder 'landings'; publish to www.mywebsite.co.uk, subfolder 'landings'. The old web files are overwritten by both the export and publish actions. Use control F5 to refresh live website to ensure viewing latest files uploaded. Tada!
Tx again for all the support you've given me!