UK paper's backers are so obsolete! (6,3,5)
I believe the answer is:
behind the times
'obsolete' is the definition.
(thesaurus)
'uk paper's backers are' is the wordplay.
I cannot quite see how this works, but
'paper' could be 'thetimes' (The Times is a newspaper) and 'thetimes' is found within the answer.
The remaining letters 'behind' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'so' is the link.
Can you help me to learn more?
(Other definitions for behind the times that I've seen before include "no longer seen as old-fashioned" , "not being updated?" , "square- with 4a" , "Old hat" , "John Walter was, originally" .)