Plastic sheeting was in place for over 24 hours, and was removed last night because of the forecast of rain. There isn't a hollow anywhere! I reckon this is + or - 2mm from level over the entire 30 sq m., other than the 2 holes for electrics boxes.Plastic sheeting over the top missing.
And there's a hollow forming in the top right-hand corner. About three feet in.
Not a bad attempt at covering up your tracks & the Father-in-Law though.