Website: http://www.thetrainingshop.co.uk
I'm having an issue after Step 4 of the checkout process whereby, quite randomly it seems, the jquery error message "Warning: shipping method required" sometimes prevents a user from completing their transaction. I use 'Total Based Shipping' which provides excellent options needed for the website - this is set up correctly, along with all Geo Zones, Tax Classes and Tax Rates.
This only seems to happen for logged in users, not guests and only when they go back and a modification is made before final payment is selected:

I urgently need some help fixing this issue. If interested please either reply to this post or email me - mac@agcdesign.co.uk so we can discuss rates/options.
Regards
Andy Cameron