Any long haul cruise flights will be in the winter season with the odd few finishing and ending in April and October (summer season) usually the Princess cruises, rather than P&O or Ocean Village.
Whilst plans change I have seen preliminary S11 brochures and there isn't any great changes in the long haul plans for then either that include CWL.
CWL long haul was always full when I operated it, so it is surprising it doesn't return although we don't know what yields they were getting on those flights and people(majority) will travel if they really want to fly long haul I had a family from near Cardiff on my Gatwick-Cancun the other week when they had the option of BHX, so it does proove that yes there is a market in CWL for long haul but the people will travel.