Difficult to say where RiverOak plans to source their cargo. USA, China and Africa must be somewhere in the mix. Cargolux may well return as they have been seen to use Luxemboug and Stanstead. The African freight was mostly veg and flowers. Flowers do not weigh much but take up a lot of volume. It is all speculation until RiverOak make more information available.
I see it has been mooted that there may be a "limited" RAF return as a dispersal site. That is a distinct possibility, been there, done it, got the tea shirt. That would really upset the nimbies, military aircraft are not required to comply with noise limitations.
Also MAY see a return of airsea rescue. Other possibilities are channel surveillance, and air ambulance. Time will tell.