It was 2.5dB when I left the house today (2nd Jan) . . .
Perhaps you meant 2nd February?
According to the OR engineer we had out other day it should be at 6. Not sure if this is acceptable being at 3 but the little I know about ADSL tells me it's not brilliant to have an SNR number of 3 or less over a 5km line
The target SNRM is usually 6 dB but if you are not noticing any problems then let it be.
(I'm just wondering if you are within the catchment area of
Walter's Wheelbarrow, as I'm sure he would be interested to see a native FTTP installation taking place.)