First few hours of FTTC

[#1]

Mr. ( its not on my job-sheet ) BT left at around 12 ish this morning after a long winded affair installing
FTTC. 
Inital test showed the full 40 up / 10 down as expected.  A 'proper test' afetr install showed 38 / 8.  Inital conection speedtest showed 30 / 7
One hour later I'm getting 12 / 7     
Should I be doing anything ?  has it gone wrong ?  or is it still 'learning'  ?
Thanks.

[#2]

I believe It can jump around in the first 10 days, after that it should settle down.

[#3]

ok.  maybe I jumped the gun...
Just plugged the laptop straight into the Netgear and got......


20 ish over wireless but only 14 / 15 over the 200mbps  HomePlugs   

[#4]

that's good to know