I don't know where I've gone wrong. I've completed all the down clues and everything seems to fit BUT . . . I have two clues that have used RI and no clues that have used RM
I've checked and rechecked every one and can't see where I've mucked up.
I'm then left with 3 "ordinary" clues (I've used all the ?R combos):
22a (Posh car's two birds - (6)) - which looks like an obvious luxury british car marque but can't see how it relates to two birds
34a (Note to look up recording that's not around USA oddly (4,5)) - although I have a couple of phrases that would fit, none seems to fit the word play or definition
60a (End of branches regularly block the way (6)) - again I can see an obvious answer that fits a definition of "way" - but can't see the word play