I have a ticket open (#167429159) but not much progress there... at the opposite, after the Openreach engineer visited and failed to find any fault, things got much worse.
Now even if I use the openreach modem + my router, once a day my connectivity "freezes", meaning I am unable to browse the internet. As a workaround, I had to create a cron job on the router that tries to ping the Google DNS every 5 minutes and, if it fails, performs a "network restart". Of course this cannot be a long term solution.
As I have not received any response in the past few days in the ticket, I hope some kind soul from the Plusnet staff would be willing to help here.