Thanks again, tatters - i enjoyed it, but I'm wondering about the apostrophe that's needed for the extra-letters clue to work.
Is that strictly fair? I mean, if the setter had written out the clue, the apostrophe would have to be included (I think) but when it's us having to punctuate it, is that ok?
Then I realised that the extra letter at that point in the clue actually has an apostrophe ('s), so are we dropping the letter plus the apostrophe? (and is that ok?).