(26 Dec 2017, 9:52 pm)South Tyne Lad wrote Irrelevant to the terminating point up north, But I'd Imagine a Teesside-Leeds service to receive more patronage than a Teeside-York one, York is more of a sightseeing hotspot for a more older market, While Leeds is more suited to the younger generation of Adults and Children too, These will attract the most revenue in fares.

You already have the X62 linking East Yorkshire and the new X10 linking South Yorkshire to Leeds, And Transdev are actively expanding there Cityzap brand out of there quite fast ( Id imagine a North East service is being looked at in some way or another by them ) so Stagecoach should atleast cover that by running there ( York can be called at pretty easily on the way too )
Running weekly is pointless in my opinion, In a perfect world it should be a daily service not leaving too early so connections from Stagey's local network can be made, But too late to not have a too short time in Leeds either, Makes more use of 54045 too.
Quite a few populous villages/towns along the A19 corridor that could be served too, Northallerton and Thirsk are not too far off the beaten track and are not served regularly by NatEx, Aswell as the trains being more expensive than bus.

Both cities seem to be booming at the moment. York has the two universities which boosts visitor numbers and city centre footfall. Leeds too.

I agree that Thirsk and Northallerton could be potential stops for the new rumoured service and I think a regular service (like you mention), could tempt punters off the train - particularly with stations in both towns being a little way out of the centre.
However, new housing on the outskirts of both Thirsk and Northallerton is attractive for commuters using rail, so part of me thinks the bus may be too little too late.
Frequency may win over an attractively priced bus ticket, for a service that may not run too frequently.

I am puzzled as to why the likes of Transdev haven't pushed further north. There could be a number of reasons, such as concentrating on their trans-pennine core.
By purchasing the likes of Rosso, it can improve connections with the Manchester City Zap service and in turn see the feed-in at either end of the route improve.
Is there scope to do that beyond Harrogate, Wetherby and York?