Never, ever sign off a letter dealing with legalities or other business with "Best regards". You may as well sign it off with "Love and kisses". 
Always address this type of correspondence with "Dear Sirs" and sign off with "Yours faithfully".
Dear Sirs is my usual prefix. Thanks for the correction on the sign off, I should start adopting this standard.
Back to the issue at hand... I have it on good authority from up on high after querying this:
Q) Should the defendant write to DCB Legal and request that they file an N279 and serve it?
A) Nope. No need. Their letter is sufficient for the defendant.
Thank you very much, I think this thread is safe to close now.
I asked ChatGPT this earlier and it told me it was not required, but I was not going to rely on it
