Contact from cPanel

[#1]

I have had a Plusnet email account for many years and am still waiting to hear from Greenby regarding the transfer. In the meantime, my email account continues to operate as normal. 
Two days ago, I received an email from a hosting platform called cPanel telling me that my mailbox has reached 97% of its 1000 MB capacity and that I need to delete mail items to prevent future loss of emails. I have never had any previous dealings with cPanel and I don’t know how they have got hold of my Plusnet email address. Might this be something to do with the Greenby transfer? Might it be a scam? I have, of course, not clicked on any of the links in the email as a suggested way of deleting my mail items. I have deleted some manually, though.
Can anyone advise, please?

[#2 · Accepted solution]

A number of observations…

1. Plusnet does not use cPanel
2. Plusnet utilisation warning emails are for the account, not a specific mailbox and are sent to the account holder 
3. Plusnet’s utilisation reports do not advise of percentage usage- they report the size of the five largest mailboxes and the total utilisation
4. Plusnet warning emails do not contain login links
5. If you have not received an email from Plusnet that you are scheduled to move and then you have been moved, you will not have had communication from Greenby

This sounds like yet another scam merchant attempting to fool people during a period of change.

[#3]

I've just returned to PlusNet after 13 years away in a rural not-spot where I was forced to use a mobile internet connection.

I gather that for a time a company called Greenby has been handling PlusNet email. 

Normally I would say, cPanel is software used by hosting companies that allows their customers to manage their accounts.

The most likely explanation for the email you received is that you once registered a domain and set up a mailbox using that domain, perhaps whole a customer of Greenby.

Obviously, that's not quite the position, but it does sound as if Greenby is continuing to store duplicate PlusNet emails of yours and that's why they report a full mailbox.

What's been going on while I've been away. (They sold up to BT for one thing.) 

[#4]

@NorfolkGreg As stated by  @Townman , not all email accounts have been transferred to the Greenby platform - in fact only a couple, if that, of the very old legacy have been moved. As he says, this sounds like spam. 

Your presumption is incorrect.

[#5]

@AlanH2 I get endless Cpanel emails, they are ALL SCAMS!

I do not have a PlusNet email address and the emails services I use do not use Cpanel either!

[#6]

It does though seem well beyond coincidence that a large number of addresses in the form of [username]@[username].plus.com or postmaster@[username].plus.com have become Spammies hot target at present.

Always targetted but filtering is broken ?

Data leak ?

Deliberate targetting ?

[#7]

Such email accounts are readily identifiable from the multitude of data breaches which have been reported by Have I been pawned.