aex: there is no information about London City operation.
anyway, the story that I know is that Aria is bankrupt, and SkyHandling took over the outsource handling service from Aviation Resources (WX-AF/KL operation).
Aria Logistic still handles all the Airlines that operate from/to LCY. In addition they have got BA City flyer and BA mainline for NYC. All dedicated Uniformed Front-Line Team & Ticket Desk.
It seems that as operational Team they still separate but under the management is the same
Is not very clear yet what's behind this strange story.