This seems to be a common thread at the moment, and I would like to add my issues to the pile.
I upgraded to Infinity 2 in April and didn't notice any speed increase at all, so I contacted @BTCares on twitter and requested further information on whether I should have seen a speed increase going to Infinity 2. I am currently receiving 20/5.
According to @BTCares my IP Profile speedtest shows that there are no issues, BUT my IP Profile also shows no change from Infinity 1.
I've spent a little while on the telephone now to a BT representative questioning why I signed a contract for a further 12 months one the premise that my internet speed would be "up to" double what it used to be on Infinity 1, only to receive no change in the service that I used to have.
A fault was eventually logged after I was informed that there was a fault at the junction box near my house. I received a link to an online fault tracker, which I watched closely.
The BT rep called me back today to tell me that a home visit is now required as the fault cannot be rectified at the junction box, even though the online tracker hadn't changed.
So, a home visit is required to fix a reported fault at a junction box?????
Anyway, an engineer is coming next Saturday to do what, I am not sure, but we shall see.
Might help to post your ip results. Honestly, if the engineer finds no fault on your line and you are only getting 20mbps now, then upgrading wont make any difference at all as you are already getting the max your line can support.
I'm speaking from experience of being on Infinity since last July.
In May this year, I upgraded to Infinity2. I didn't get any increase in speeds.
I never got more than 30mbit down before the upgrade. However the speedchecker was now showing that I could get 41.4mbit down.
Even after an engineer visited and did a sterling job of getting me onto a new pair with better snr, I am only just managing 34mbit down.
1. If you never made the threshold of 38.7mbit down on Infinity1, you may not see any benefit going onto Infinity2.
2. A combination of distance from the cabinet and any aluminium cabling in the service can affect the VDSL signal