They're used by late entrants (6,5)
I believe the answer is:
pearly gates
'late entrants' is the definition.
The definition suggests a plural noun which matches the answer.
'they're used by' is the wordplay.
I cannot really see how this works, but
'by' could be 'at' and 'at' is found in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for pearly gates that I've seen before include "entry to paradise" , "That may be experienced after 'death rattle'" , "Place of judgment" , "Entrance to heaven" , "Heaven's entrance" .)