I did this on Sunday. Turned up to inspect a 3g pitch which had 2 cm of solid ice at corner flag. I waited til 0920, kick off scheduled for 9, but no thaw so called it off. Felt sorry for travelling team so I waved him half fee, only to be challenged by a parent "your not putting this off are you? At least you'll get your 20 quid" he said. Just can win