it's a themed one ....entry is an anagram of in(p)ut
If you put the 3 letter theme word in front you get the regulator
Have you got 23a or 32a? I have most of the letters and can see answers that would fit bt can't see a parse for them...
23a See model, not giddy on vacation (4) T?IG twig ??
32a Recollect the ancient ocean city (6) NIA?ER
i have only 5 themed so far so one of them could be the other??