Here's the thing,
P&O simply have had to go to Maleth (who >?
you may ask lol) as there are NO spare long haul charter aircraft
anymore in the UK......
As for the Maleth bad reports of the 'soft product'
yes true,
P&O could have simply arranged for an
enhanced catering on the meals, and perhaps offered free drinks (but they maybe free already anyway?)
Also ensure a pillow and a decent blanket
on each seat.
We used to have for our cruise flights for P&O, or Cunard
logo headrest covers on the seats - All small things
, but the Pax do notice.
Having no IFE is pretty Naff these days on a Long haul flight, but many folk will bring a book, and a Pad to watch content,
but there is NO at-seat power 
......
So there we have it...
Edit - also Maleth fly their A330's in a very nasty 3-3-3 config at 345 Y (remember Monarch's A300's with 361 seats yuk)