At about 00:30 today my connection dropped for a few minutes and then came up with connection speeds of 79999/19999 (previously 77934/19999). Some of the G.INP settings have changed a little, and in particular the downstream bearer 0 interleave depth has increased from 8 to 16. The downstream SNRM has dropped from 6 dB to 5 dB, and the attainable downstream speed has increased to over 80000 currently.
Previously the connection was totally stable and the ES levels were only about 6 ES per hour. So it looks like a bit of G.INP optimisation, although I have no idea what initiated it.
None of this has any significant practical consequence for me, but it's a curiosity, and it would be interesting to work out what's happened.