It is indeed old, but I cannot see that anyone will mind.
Quite a nice increase there, though I would like to see some stats from your router because of the potential oddities with BTW speed tester.
If the sync speed has increased, could be one or a combination of different things. The DLM may have lowered the SNR, removed banding (if applicable) or perhaps your modem resync'd after a power cut (so less interference
). Though if it is the latter as opposed to the DLM making changes to your parameters, then you will probably lose it after another resync. So let's see those stats!