6000PIC
Fairly common practice these days for Charter airlines to get crews to operate out and deadhead back on the same aircraft, commonly a end of season thing. OK it might not be nice roading it to CWL and then paxing for a total of 19 hrs but its again a fairly common practice for "lean and mean" Companies.
Whichever way, the CAA are not interested in the stuff above, it's all legal (but not sociable i agree)