I've been in touch with Tim Moorey who has confirmed that the answer is indeed an anagram of "when dancing" which unfortunately has 1 "n" too many. emeritus has it right.
Thanks for clarifying the error in the clue.
I am wondering if Tim Moorey hasn't also made a mistake with the
instruction re the highlighting of 'numbers' ?
I'm also totally lost re the numbers. Whether the instructions are erroneous or not, I can do no better than quote Tim himself - " I miss my wonderful checker who kept me honest."