Dear bt
I hope all is well
This is just a customer to customer help forum, everyone here, including myself, are just customers.
The only BT Employees are the forum moderators.
As you already have full fibre 100, then there will not be any change of equipment, as its only a profile change.
You are unlikely to see any increase in the wireless speed unless you have devices capable of a faster speed, and are very close to the home hub, but you should get the full speed on devices which are connected directly to the home hub, and are capable of faster speeds.