Apostatism is definitely a mistake that has now been solved, and chambering ( word in Romans ) fits neatly into the archaic definition of illicit sex, hence wanton behaviour. I have worked out 27 ( a cheeky homophone trap! ) Thanks all!
If you have a copy of the Chambers Dictionary and use the Chambers website you will be able to complete this quite quickly. It's quite easy this year and I completed it after two days. Remember to identify the homophone clues.
Agreed that apostatism is wrong. I've got it now and am left with that one teaser, 28c: I??ERC??? ( Chambers whiz gives me INHERCING, but I cannot rationalize it yet! )
Mallyh, seeking the rationale for INTERCITY...in Britain, the word intercity denotes a fast train, so that could be it!
Congrats to Heaton21 who was able to complete it in two days!
I will research the Chambers website!