relay.plus.net server not available blacklisted by local policy

[#1]

Hi

My mailserver is now unable to send emails to relay.plus.net from a static IP address supplied by plusnet (80.229.28.147).
It has been working fine for many years until a couple of days ago.

Email rejection message shows:

host relay.plus.net[212.159.9.107] refused to
    talk to me: 554 avasout-ptp-001 smtp ESMTP server not available
    (blacklisted by local policy)

I have tried a telnet test from mailserver which shows similar error:

telnet relay.plus.net 25
Trying 212.159.9.107...
Connected to relay.plus.net.
Escape character is '^]'.
554 avasout-ptp-001 smtp ESMTP server not available (blacklisted by local policy)
Connection closed by foreign host.

I have checked my static IP address against blacklists such as on https://mxtoolbox.com/SuperTool.aspx?action=blacklist%3awww.matros.co.uk&run=toolpage  , and all clear (now..I had to clear from spamhaus, but that was over 4 hours ago...perhaps plusnet only fetches blacklists every so often...if so, how often?)

What set of blacklists do plusnet use (that I can check)? or is there another problem?

Worryingly, I phoned plusnet support, who whilst very polite, after 30 minutes or so , said they couldnt fix my problem...try the community..

[#2]

Moderator's note:
Post released from the automatic Spam Filter.

[#3]

@matwillis do you send large quantities of emails in short timescales from your server ?

[#4]

No, just one or 2 emails per day from 3 domains linked to this IP address

[#5]

@matwillis thanks, so its not that youve tripped the sender volume limits. Its that your IP is blacklisted for some reason

I have checked my static IP address against blacklists such as on https://mxtoolbox.com/SuperTool.aspx?action=blacklist%3awww.matros.co.uk&run=toolpage  , and all clear (now..I had to clear from spamhaus, but that was over 4 hours ago...perhaps plusnet only fetches blacklists every so often...if so, how often?)

It MAY be that PN havent yet noticed you're not on the blacklist any more.

If it doesnt clear today, then you have two alternatives,

1) contact support and tell them explicitly

"Plusnet's SMTP server is blocking my PLUSNET STATIC IP address - can you please raise a ticket requesting second line investigation".

2) wait for a PN help team member to pick this thread up and do similar