This is a BT residential customer to customer forum. Your post does not go to BT. The only BT staff are the forum moderators who do not necessarily read all the posts.
If you want forum members to try and help can you run this checker and post back a screen shot of the results
and use this speed tester then carry out the further diagnostics and post back a screen shot of all the results including your IP profile for up and down. This test must be done with a wired connection.
I presume you will have a Homehub 5 so can you also post the stats from 1-12 by logging onto the homehub management pages then troubleshooting > helpdesk. http://bthomehub.home/
If you can carry out the tests that I requested, they are simple to do, and once they have been done it may be that it is an easy fix or at least it can be diagnosed so that you know what the problem is when you contact BT.