Ban on sailing vessels turning up and dropping off children is to remain after all (4,2)
I believe the answer is:
stay on
'remain after all' is the definition.
'stay on' can be an answer for 'remain' (synonyms). I am not certain of the 'after all' bit.
'ban on sailing vessels turning up and dropping off children' is the wordplay.
I cannot really understand how this works, but
'on' is present in the answer.
The remaining letters 'stay' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'is to' is the link.
Can you help me to learn more?
(Other definitions for stay on that I've seen before include "Remain after others have left" , "Remain behind" , "stick" , "Remain after normal time" .)