Out of interest, are the East and West editions done completely separately? I just watched the two side by side and obviously the backdrops are different throughout, but there are clearly bits which are identical. Presumably they prerecord one edition completely, do the second one live, but drop in bits from the first prerecord.
The location reports are obviously shared - but all studio elements must presumably be repeated because the backdrops are different. Also - keep an eye on the script colour. I think one edition is on pink paper, the other on yellow - presumably a sensible decision to avoid confusion between shows.