BA cancelled a number of flights by accident a few days ago, they then re-instated the flights, and presumably they are trying to persuade the robots to put people back on their original flights. This is probably going to be caught up in the LHR versus LGW debate, which will probably surface at some point, and my crystal ball suggests that in fact the LHR service will get cancelled if all works out ok in the months ahead.

You don't really need to do anything, but it won't harm you to ring BA to get yourself back on the MCO service properly, they may need to revalidate your ticket. The robots may do it anyway, and if LHR goes in favour of LGW then it would happen anyway (and you could have a refund potentially).