Thanks for running the speed tests. Usually if the sync speed increases, however there is no increase in throughput speed then we advise switching the router off for a full 30 minutes (only do this once) as this will reset the current session and can often increase the throughput speed.
Just to confirm, have you tried this since the sync speed increased?
Glad to hear there's been some improvement. Regarding compensation, could you contact our Customer Services team, please also see our Complaint Process
I don't know specifically what the problem was. DLM adjusts the profile based on the number of errors and/or disconnections so if it moves you to a slower profile either the disconnections or errors have fallen outside acceptable limits.