Here’s the update I said I would give around 10 days after I downgraded from Infinity 2 to Infinity 1.
Unfortunately my connection did not sustain the 51.5 Mbps it peaked at the day after the switch. But it seems to have settled down to just under 49 Mbps – at least it’s been steady at that rate for the past 4 days since the DLM recovered from what appeared to be a bit of cardiac arrest, dropping the speed to 40 Mbps!
Here’s an illustration of my connection profile over the past year or so according to Ookla. It comprises over 130 test results stretching from the end of March 2016 until now. Pretty constant at just under 46 Mbps until the ‘downgrade’. (The other large temporary drops in speed might have been due to me not disconnecting the VPN before testing.)
So the result in ‘downgrading’ for me seems to be a win-win – over a 6% increase in speed and almost a £140 cost saving over 12 months (at least at standard prices).
However I remain puzzled as to why the DLM got stuck for almost a year when the line appears quite capable of sustaining a higher speed – albeit not the 60 Mbps I enjoyed for almost 3 years after initial connection.