Migrating Domain Email From PN

[#1]

I have had a domain for decades and it has been hosted on PN for almost the same time.  I want to move the mail to an external host.  When originally set up I just used the PN servers for so everything went to PN.  I  need to prove to the perspective mail hosting provider that I own that domain by the use of a text file that you cannot do with PN.  Now what I would normally do is set the name servers to my registrar, so that I can add the txt file to their servers, and then point the MX to PN servers.  This should enable mail to still be received by PN until migration and for me to access it during that time.  However, there maybe issues within PN doing it this way. 

Has anybody experience of doing this with PN?  I have done a search on the forum, but so cannot find anything.   I also need to confirm with the perspective mail host that they migrate the mail that is currently on PN.  Their site indicates that the usually can, but don't mention PN.

[#2]

What you need to do is to transfer your domain name to your chosen registrar and administer the domain there.

If you are moving the hosted services (email and web) elsewhere there is no merit (sense) leaving the domain registration with Plusnet.

You can arrange to move the domain registration whenever by asking Plusnet to change the ISPTAG on the domain.  Everything will continue to operate as is UNTIL you change the name servers away from Plusnet.

[#3]

@Townman I possibly didn't make myself clear.  PN is not the domain registrar, that has always be elsewhere.  However the domain email, and at one time the website that is no more, was hosted by PN.  (In those days it was easier to just allow PN normal servers to receive the mail, etc,  and IIRC was what PN wanted over two decades ago.)  That is why I said "what I would normally do" etc. (I would never have a domain registrar, and I still have a few, the same as the web hosting or email hosting company.)   Over the years there have been a few peculiarities with PN.  What I don't want to do is set the MX at the registrar for the domain to PN servers, and then find for some internal PN reason the domain email is being rejected, until I am ready for that to be received by the new mail host.  What I am really asking is have others had issues?

[#4]

 Now what I would normally do is set the name servers to my registrar, so that I can add the txt file to their servers, and then point the MX to PN servers.  This should enable mail to still be received by PN until migration and for me to access it during that time.  However, there maybe issues within PN doing it this way.

@Total_Chaos AIUI that WILL cause problems, I don't believe PN will receive mail for a domain UNLESS the nameservers are set to the PN ones, even if the MX record points to the PN servers. Maybe @Townman can confirm that ?