This is the email from Nexus:
"There are changes in the pipeline for services 79/79A due to a commercial registration by Go North East to which Nexus is reacting to ensure local links are maintained, but we don’t have a final situation yet. As this stage Go North East has declared an intention to partly replace service 79 from 31 May by extending service 238 to Barnwell during the day. We have as a result, and to hopefully make things clearer for passengers going forward, tendered evening and Sunday journeys now covered by services 79/79A numbered as services 238 and 239 at this stage. We are at this stage awaiting further detail from Go North East and timetables – and indeed the route numbers - can only be finalised when we have this."
RE: Go North East: Upcoming Service Changes