The 15 becomes a bit more unique.

Until 31st August, Stagecoach service 15 between Bilton Grange and Hull Paragon Interchange almost entirely overlapped other routes, either service 13 around Bilton Grange or multiple other services along Holderness Road. The only 'unique' section was the very short Diadem Grove in Bilton Grange, which is within walking distance of other stops. The main purposes of the 15 were to provide a fast link from Bilton Grange to Holderness Road Shops and Hull City Centre (as compared to the 13), to link Bilton Grange to parts of Holderness Road north of Southcoates Lane (e,g, East Park and Morrisons) and to form part of the wider Holderness Road service provision.

Since Stagecoach's service changes at the end of August, the above still applies, but not quite to the same extent. Rather than operating the same clockwise loop around Bilton Grange as the 13, the 15 now omits the southern most section of Barham Road and instead operates a slightly longer loop around parts of Staveley Road, Hopewell Road and Amethyst Road back to Barham Road. The section of Staveley Road is otherwise only served by hourly route 40 and the section of Hopewell Road now covered was previously unserved. Small change, but better coverage of East Hull and a slightly increased 'purpose' for the 15 - no bad thing as it hasn't recovered back to it's old Monday to Saturday daytime 15 minute frequency prior to the 2022 Stagecoach strikes, instead operating every 20 minutes Monday to Friday daytimes and half hourly Saturday daytimes.