I had a ticket open (#38311020) from 26th December & got email notice of updates up to 07 January, but didn't get any emails for replies on 10th,14th & 18th (lists my hotmail in text in the first entry).
Subsequently I raised a fault (#38867440 - no line to indicate email address but that may be because of the different route into the system). I'm pretty sure any email notification box was ticked but I didn't receive any email notifications. Or is there a box in the fault/ticket system to put in an email address - in which case I almost certainly put my gmail one when I raised the fault.
(I should note that to Plusnet's credit I DID get texts & phone calls as the fault progressed through the system).
It could be a case of hotmail randomly ditching plusnet emails so I have changed the secondary email address in my details from my hotmail - as I've known emails to hotmail to randomly get blackholed there before* - to my gmail account but can't remember if I did it before the fault was raised.
(*the service status ones used to go to my hotmail but randomly stopped never to reappear but have been fine since switching it to gmail).
"If I have not seen as far as others, it is because giants were standing on my shoulders."