The new service 255 journeys come at the 'expense' of some of the 250 Humber Flyer 'shorts' between Hull, Barton and Humberside Airport, but I'm not sure this will be a huge issue as I often see the 'shorts' arriving and departing Humberside Airport empty, or almost empty. Service 250 journeys withdrawn, all Monday to Friday only, are the 0645 from Paragon Interchange to Barton Market Place, the 0825, 1425, 1630 and 1730 from Paragon Interchange to Humberside Airport and the 1525, 1740 and 1840 from Humberside Airport to Paragon Interchange.
Reviewing in more detail the changes and their impact on the overall Hull to Barton service, the first service from Hull to Barton will be 15 minutes earlier than at present with the 0605 service 255, but there will be a 35 minute gap between the 0620 and 0655 service 350 departures from Hull to Barton - probably not a significant issue at that time of day. The new 0605 presumably works 'onto' the 0723 Barton Market Place to Hull service 250. The replacement of the 0825 255 with the 0805 250 is a very slight worsening of the Hull to Barton service at this time of day, which fits in between the 0755 and 0840 service 350 departures from Hull to Barton, but again probably not a significant issue at this time of day heading out of Hull. The 0805 service 255 presumably works 'dead' upon on arrival at Wren Kitchens to Humberside Airport to 'pick up' the 0925 service 250 from the airport to Hull.
In the afternoon, the 1425, 1630 and 1730 departures from Hull Paragon Interchange becoming a 255 rather than 250 means they will not serve the Interchange, Butts Road or Pasture Road in Barton, which is unfortunate and does slightly undermine the afternoon every 15 minutes service from Hull to these areas of Barton. Three buses an hour is still very good though. Likewise replacing the 1525 service 250 from Humberside Airport with the 1550 from Wren Kitchens not serving Pasture Road, Butts Road and Barton Interchange, and also serving the opposite side of the Market Place to other 'Hull-bound' journeys, does 'spoil' the 'headline' 15 minute service, but in this direction at this time of day, I don't think it's a major issue.
The replacement of the 1740 and 1840 service 250 journeys from Humberside Airport with the 1720 and 1810 service 255 from Wren Kitchens is actually an improvement between Barton and Hull however, as between Barton and Hull these 250 journeys had been leaving at the same time as service 350 journeys, but will no longer do so.
Last year Wren Kitchens received approval for a new factory adjacent to their Barton HQ which will generate an initial 525-535 extra jobs, potentially rising to 1260-1285 extra positions. The planning application economic impact assessment noted that in April 2019, Wren Kitchens employed 1551 people at Barton, with 807 (52%) living in a HU (Hull and East Riding) postcode. There is an existing market for Stagecoach to serve here, and one that will grow significantly when the new factory opens. With largely concentrated shift start and end times, it seems ideal for commuter bus services, and any reduction in cars travelling through Barton Town Centre is very welcome on air quality, congestion and safety grounds. On an anecdotal basis, my personal observations are that there is a near constant flow of vehicles coming off the Humber Bridge through Barton to Wren Kicthens around 0630-0640 each morning. There is also a lot of vehicles leaving the site around 1730.
Hopefully the 255 will provide some useful 'contraflow' traffic to the overall Hull to Barton service and help ensure the success of Stagecoach's increase of the Barton to Hull service to four departures an hour Monday to Saturday daytime.
The 250 Humber Flyer journeys serving Grimsby and Cleethorpes are unaffected, as is the Saturday service.