No way would Network Rail allow TPE to chop 12 minutes (44%) off the turnaround time of the South TPE services, with potential impacts on the WCML, MML and ECML punctuality performance. As
@Killingworth frequently reports, performance on the Hope Valley line is already amongst the worst in the country. The crossing moves between Piccadilly and Stockport would be exactly the same as now, because Piccadilly P9/10 are the only platforms available for these services to use.
Since May 2018 TPE has been forced to extend turnaround times and add diagrams to its North services to increase recovery time. The Newcastle and Redcar services now have 40 minute turnarounds at the Airport.