Might be different for ADSL24 than for BT Infinity. As BT provide the router in advance with correct login etc ready installed, the Openreach installer can usually connect it and check out 'real' internet use.
I think ADSL24 don't provide a router, but leave it the the user to provide one (or do PC pppoe connection). Setting that up is probably beyond the installer's remit (and beyond their capability for many of the outsourced contractors).
Moved (with trepidation) to BT Infinity 2 for upload speed. Happy BE user for several years.