When was it that the 180s ran to Hazel Grove? I believe Hazel Grove was wired to clear Stockport of reversing EMUs, in the same way as Blackpool North was wired more to clear Preston of reversing EMUs than being a particular priority for electrification being a dead end branch. The Hazel Grove wires end so abruptly, with no overrun at all.Speaking of former cases I recall for a while a few years back the hazel grove line was operated mostly if not entirely by diesel, after the prior buxton to blackpool and hazel grove to manchester services were replaced by buxton to manchester and hazel grove to preston services. I think this may lasted until the line to preston via bolton was electrfied.
When this first started there was one electric train a day "to clean the wires", but IIRC even that dissapeard later. I'm not sure what happened on weekends.