CityFibre site (and Toob) say I can connect, previous owner says I can't...

Just moved into a new property. Can't get my old provider Virgin here as the property is set back from the main road. Old owner used Talk Talk but they sound rubbish.

There is a CityFibre black box in the property, and brown box outside the property. Previous owner said they put these in, but repeatedly came and said they can't connect them to the network due to the house being set back from the road.

However, the CityFibre site says I can connect, and talking to Toob they are ADAMENT they are available to me.

Issue is the next install date is a long way away and I can't wait that long if they are just going to come and say they can't connect me.

Who should I trust?