Surely in 13a there has to be an indication to remove the first letter? Also, have never liked 'perhaps' as an anagram indicator - 'strange' or 'unusual' would have worked better in this clue, imo.
As Mamya said, it's one of Goliath's favourite tricks & a legacy of the dreadful (IMO, I know I'm in a minority) Araucaria & his "let's make the rules up as we go along" style.
Scottc, welcome to AnswerBank; it is better to scroll down to see if the questions have already been answered before posting (some of us have previous for not not doing so - hands up me).
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