Thank you.No law against coasting!
I would coast if, a) I didn't have the right gear for the hill b) If i needed to slow down / manoeuvring or c) I needed to recover as my pacing was off
Given the description of your course it sounds like you could be losing time on these sections.
NB I have heard that keeping the legs spinning, even if not pushing out power, helps clear the lactic acid.
Good luck on your next attempt.
Will give this week's event a miss due to England Belgium but hopefully by next Thursday will have had several rides without any huge gaps in cadence and see if that makes a difference.