@davejones7836
If you have read some of the other tales of woe reported by eager new customers on here, you will find you certainly aren't alone and, alas, the usual advise is to decide for yourself how much leeway you are prepared to give them and after that just assume they don't really want your custom and look elsewhere!
Now firstly, it is possible it will still all take place today (actually it probably won't), do you have an internet provider in place at the moment? If so then whatever happens don't cancel it until (if) VM actually install as the current record for delay between first promised installation date and it actually appearing is over one year (and I think, still counting)!
I'm sure that for the most part, installations probably just go ahead on time with no fuss and all works - the problem arises when something even slightly goes pear-shaped, at which point VM's response has all the grace, efficiency and speed of an arthritic sloth pulling a fully-loaded truck up a steep hill, in the snow!
Neither will you get any explanations as to why it is delayed - truth is VM don't know, aren't in a position to know, and frankly aren't overly bothered to find out anyway. The hoary old excuses regarding, 'council permits' or 'permissions' may get trotted out plus the fairly meaningless 'extra work is needed', to which the obvious answer is 'fine, so why aren't you doing it?'
So, you work on the basis that in all likelihood, you will not be getting VM internet today, or possibly for the foreseeable future, what do you have in place now to tied you over? Can you get a temporary 4G or 5G router on a rolling monthly contract? If you want, then you can certainly try chasing it up each day, an experience which I'm sure appeals greatly to anyone with masochistic tendencies.
Like I said, set yourself a time limit, after which just forget about VM and sign up with an alternative supplier, as a tip DON'T actually cancel the VM install, let it go ahead but as soon as it is in and proven to be working, immediately cancel within 14 days at no cost to you, but you will be sure that the connection is there and good should you want to give VM another go in the future.