Based on the usenet speeds you mentioned, i'd say you have the full 38717/10000
I would think that's about right.
I estimate my cable length (to the cabinet) to be around 200 to 400 metres (depending on the road/path routes used from the cabinet round the corner, and taking into account the order in which they built the houses), the 400m route is the less likely, as it would have involved routing phone cables through a part of the estate which wasn't built yet. The most obvious route is 275m.
So I should get maximum speed on the current profile and a bit higher when BT switch to 17a. It's just a shame the engineer was either unwilling or unable to tell me the actual line length, or the sync speed.
vDSL2 FTTC Infinity with BT
DL Sync not a clue, but DL speed is around 37Mbps
UL Sync again; not a clue