Fibre Speed

[#1]

I've got FTTC at the moment, currently my IP Profile is set to 54.45 Mbps (Very stable)
However my next door neighbour, has asked me to check what speeds they'll get and both BT & PlusNET have said they'll get between 63Mb-80Mb.
Can PlusNET increase my IP Profile? so i can get that extra 10 Mbps? or is there a reason it's set to 54Mbps
FTTC Range A (Clean) 80 63 20 20 -- Available
FTTC Range B (Impacted) 71.7 44.1 20 15.4 -- Available
Very confused 

[#2]

It's set at 54Mb because that's what the DLM system has determined is the best speed for your line - it's currently syncing at the highest speeds we've seen so far, going back as far as September.
Not really sure what to suggest in all honesty as the usual master/test socket tests etc don't really work on Fibre. Any difference in speeds with a direct connection to the modem?

[#3]

I'm very confused, When i got FTTC http://www.dslchecker.bt.com stated i would only get upto 54Mbps.
Since then it's now stating i can get 63-80Mbps