My line used to be synced at 75 down and 20 up (I'm on BT fibre 3 package).
I'm using a Netgear DM200 VDSL modem and an ASUS router. After being rock solid after 2 months with no resyncs at 75 down 20 up, yesterday my line resynced at 79 down and 20 up. However, I'm concerned that it might disconnect or cause any instabilities. What might have caused this "increase" in sync and should I be worried?
DLM has decided your line is stable enough to reduce your SNRm from 6dB to either 4or 5dB (your modem is reporting 4.5dB so could be either) with the commensurate increase in speed. If DLM considers your line stable enough, it could reduce your SNRm to 3dB. If the line becomes unstable at the lower figure, DLM will increase your SNRm back to 6dB to improve stability.
Edit: DLM won't reduce your SNRm further as you are now syncing at maximum speed.
Ok got it, what made me worry was the fact my modem stated my line could handle a max of 75 down and 26 up, and I'm synced at a bit beyond of what my line could "handle"
Also, should I be worried about the number of Errored seconds?
What should I look out for?
Just leave it to DLM to do what's best for your line. Nothing you can do about it anyway, DLM is an automatic process.