Here they claim ... :

Only ClassicFlight and Star Alliance Flight rewards results can be displayed because the following airport – Montego Bay – does not support electronic tickets, which are mandatory for ClassicPlus Flight rewards.

But here, they include

Montego Bay, Jamaica (MBJ)

in the list of e-ticket destinations.

Typical disconnect... no ClassicPlus awards because the right hand doesn't know what the left hand is doing. And it would even be in their best interest to get their act together, because some people would perhaps LIKE to spend 348000 points to fly to MBJ.