You'll find Paphos doesn't operate November through to March. So what exactly is the aircraft going to do on a wednesday in those months?
Thomson had an aircraft at DUB in the summer that didn't operate Monday to Thurday.
Its more cost effective for TOM to ground the aircraft. Its paphas in winter its not exactly ACE, TFS where they are worm. You saving airport charges, fuel costs as well as crewing. One day not operating dosn't mean they are leaving DSA. I bet there is other bases in the UK where aircraft do operate on selected days.