The open reach guy that ran the fibre to the house said 30m plus along with this in the email from bt
On the day, your engineer can run an uninterrupted fibre cable (up to 30 metres long) to your home Hub from the box on your outside wall. This cable can only go along walls, both internally and externally, but not under carpets or floors - they may also need to drill some holes (as carefully as possible)
I think there is some confusion here and not from your end. An uninterrupted fibre cable can be any length, a data extension cable is 30mtrs (FTTC}, ethernet can be up to 100mtrs.
When your fibre is installed there will be an ONT fitted just inside where the fibre enters your premises, there will then be an ethernet lead to connect your Hub. The ONT is connected to the EZ Bend cable which has a maximum length of 2.5mtrs from the outside. There is no fibre lead to the Hub, it terminates at the ONT.
the last post made by pippincp explains what connects the out side connection to the ONT inside