Legitimate inbound email never arrives - spam filters turned up to 11?

[#1]

For the last few days i've had several expected emails never arrive to my plusnet mailbox, and giving it some more thought this afternoon - after 3 more things definitely didn't show up just today - I'm wondering if this might have been going on longer. Maybe even as much as a month?

Today I should have had emails from Sainsburys, Fasthosts and our energy company that have never arrived, earlier this week I can think of order confirmations from a couple of other shops that never came, and remembering back to a few weeks ago I had to request some GOV.UK ones be re-sent multiple times before they actually arrived.

Does anyone at Plusnet know if there have been any server changes that could have caused this? New spam filters? Someone dialled up the filter agressiveness?

Any and all thoughts welcome.

[#2]

I have the same problem with legitimate emails getting rejected and agree something is overzealous on the Plusnet side because even turning the dashboard spam filters off made no difference.

https://community.plus.net/t5/Email/Receiving-emails-from-a-domain-works-fine-for-days-then-suddenly...

Alas it seems Plusnet staff do not frequent this board very often and I will have logged a call today.

[#3]

I've turned off the spam filtering too and it has made no difference - not even for the worse; i've not had a sudden increase in spam. I suspect there is some other filtering going on.