I was plagued with disconnections. See this thread: https://community.plus.net/t5/Fibre-Broadband/Evening-disconnections/m-p/1823053
OpenReach couldn't solve it.
Still, I stayed faithful to Plusnet and on renewal of my contract, was sent a Hub Two router to replace my (second one- that didn't resolve the disconnections) Hub One.
Instantly, the disconnections ceased. Been up now constantly for over 80 days. Fingers crossed it remains that way.
I couldn't post in my original thread as that is locked but I hope this helps someone else. Thanks to Gandalf for trying to fix my issue in that thread.