Prompt Bolshevik saves time (6)
I believe the answer is:
remind
'prompt' is the definition.
(I know that prompt can be written as remind)
'bolshevik saves time' is the wordplay.
'bolshevik' becomes 'red' (type of communist or 'red').
'saves' is an insertion indicator.
'time' becomes 'min' (short for minute).
'red' placed around 'min' is 'REMIND'.
(Other definitions for remind that I've seen before include "Jog memory, cause to think of" , "Prompt; cue" , "Cause someone to remember" , "Prompt, assist someone to remember" , "Warn" .)