Latest Conservative: here today, gone tomorrow (12)
I believe the answer is:
contemporary
'latest' is the definition.
(thesaurus)
'conservative here today gone tomorrow' is the wordplay.
I cannot quite see how this works, but
'conservative' could be 'con' (abbreviation for Conservative) and 'con' is located in the answer.
The remaining letters 'temporary' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for contemporary that I've seen before include "current" , "Modern in style or design" .)