I was just reading the document and seen Nexus added this:
"On behalf of Nexus,I wish to express our support for the Follingsby Lane scheme upgrade. The projectwill improve the condition of the road within the geography and to the standard expressed in the template Transforming Cities Bid and, most importantly, restrict vehicular access to public transport and local traffic only. With the co-operation of the commercial bus operators and in partnership with IAMP LLP, thisscheme will facilitate vital public transport connections between the International Advanced Manufacturing Park, the Follingsby Max developmentand a number of local and regional conurbations. It willprovide access to jobs and training opportunities for local people without increasing road congestionand so willpositivelyimpact on local employment, productivity and economic growth.To demonstrate Nexus’ commitment to this scheme, new bus shelters with real time service information will also be provided at Follingsby and IAMP to provide an improved waiting environment for passengers. Nexus view this scheme as the first step in an ambitious wider development.If delivered to its full potential,the introduction of a local connectivity hub in the Follingsby locality will connect bus services with a local rail link, a substantial Park and Ride facility andsustainable transport options. Looking to the future, it may also become a test-bed for autonomous vehicle services"

It sounds like it's going to be a more than a quick bolt on to some unprofitable service. Notice there's a map where they want to improve
Newcastle Airport -> Newcastle -> Heworth -> Boldon -> IAMP / Follingsby -> Sunderland Enterprise Park -> Sunderland

https://northeastca.gov.uk/wp-content/uploads/2019/06/annex_for_pt_reliability_package-1.pdf - It's in there.

Guessing that's where one of the first P&R sites is planned to be aswell. Interesting choice though as it could potentially work for Newcastle and Sunderland if the buses are actually quick enough. The 'regional' would suggest that the X9/X10 is planned to go down there at some point if they can; not sure if people will be happy with that though.

Noticed in the same document they want to improve links between Newcastle -> Metro Centre -> Team Valley -> Chestle-le-Street / Washington -> Durham -> Newton Aycliffe. Could this be the X-lines X22 service was has been hinted at before.