The home hub3 is an ADSL modem/router and won't work with Infinity (VDSL) without a separate Openreach modem.
Yes I am still in contract so that's good news about the free router.
If it's definitely the router, it may well be worth me getting a spare so I'll go price one up. Thanks again, Keith
The cheap TP-Link one can normally be obtained locally from places like Argos and may be a much quicker option to get online again and prove the fault.
I've got exactly the same issue. BT engineer came this morning and found no issues inside or into the house so assumes it must be the router so no have to wait for a new one which hopefully will solve the issue, 5 days and counting without internet with teenagers over half term and exam season. Not great. Also fed up of emails from BT saying the issue is resolved when we still have no internet.