How common is an aircraft swap on these routes (and ATL)? Right now I'm between DL 30 and VS 116 (award J for 2 from RDU - ATL - LHR) which leave about an hour apart and land in London about an hour apart (DL 30 being the last departure of the night)

I'd love to try VS UC, it's been on the bucket list for a long time, but I'm concerned about the potential for an aircraft swap from the currently slated a346 to an a330 (which is what appears to be currently operating VS 116). Plus it's an overnight flight so seat comfort is probably more important (and sadly no VS clubhouse ex-ATL and there is no award availability ex-JFK or ex-IAD at the moment that works). That being said if we went with VS we could use the Revivals lounge on arrival.

This is for May 2017 so it is a long ways off but I've not tracked VS for awards before so I don't know how frequent aircraft swaps are.