Correct Installation Address - incorrect service address - Vodafone

Moving to a new address, Ordered full fibre in Northern Ireland from Vodafone. Installation address on the email recieved when ordered is correct, and when logging in online the installation address is correct.

However I just recieved a letter today and it states the address the service will be activated at is my old address, which is the registered address on my Vodafone account as I have my phone plan with them.

I called Vodafone and they weren't the most reassuring. The agent said he wasn't sure why that address was on the letter, but as long as the installation address is correct it "should be ok". Didn't fill me with the most confidence.

How likely that it was just an admin error their side? Whats the likelihood they install at the correct address, but then actually make the service live at the incorrect address?