Openreach finished. Possible to get broadband speed back - reset? Current 350k

[#1]

Hello
After multiple disconnects, due to a week of Openreach line work - finished Tuesday, I was left with a slow connection and these router stats:
DSL Type: G.992.3 annex A
Maximum Bandwidth (Up/Down) [kbps/kbps]: 1,064 / 5,348
Bandwidth (Up/Down) [kbps/kbps]: 443 / 280
Output Power (Up/Down) [dBm]: 12.5 / 10.5
Line Attenuation (Up/Down) [dB]: 28.0 / 46.5
SN Margin (Up/Down) [dB]: 25.0 / 33.0
Vendor ID (Local/Remote): TMMB / IFTN
Error Seconds (Local/Remote): 0 / 0
FEC Errors (Up/Down): 0 / 0
CRC Errors (Up/Down): 32 / 1
HEC Errors (Up/Down): 7 / 0
And a Plusnet 250kbps connection.
Today after an exchange reset? much better stats.  In an attempt to improve I tried a complete switch off and reboot of the router an hour later. I now have:
Link Information
Uptime: 0 days, 0:55:53
DSL Type: G.992.3 annex A
Maximum Bandwidth (Up/Down) [kbps/kbps]: 1,064 / 3,588
Bandwidth (Up/Down) [kbps/kbps]: 443 / 3,544
Data Transferred (Sent/Received) [MB/MB]: 2.83 / 6.00
Output Power (Up/Down) [dBm]: 12.5 / 18.0
Line Attenuation (Up/Down) [dB]: 28.0 / 46.5
SN Margin (Up/Down) [dB]: 24.0 / 15.5
Vendor ID (Local/Remote): TMMB / IFTN
Loss of Framing (Local/Remote): 0 / 0
Loss of Signal (Local/Remote): 0 / 0
Loss of Power (Local/Remote): 0 / 0
Loss of Link (Remote): 0
Error Seconds (Local/Remote): 0 / 0
FEC Errors (Up/Down): 0 / 0
CRC Errors (Up/Down): 41 / 7
HEC Errors (Up/Down): 7 / 15
BT IP profile 3126kbps  Plusnet speed 350kbps  
I understand from other posts that it can take the DLM up to 400 hours for every 3dB SNR Margin improvement.
Is there anyway, now that I hopefully have my stable line back, to get this process speeded up please? 
Derek
Edit: wrong speed entered.

[#2]

If the IP profile on a BT speedtest is showing as 3126 then you should start seeing speeds nearer to that very shortly. I've just upped the speed on our side to match as near to that as we can.

[#3]

Hi Chris
Thank you, speed now back to 3000Kbps, much improvement. 
Is there anything that can be done about the high 15.5dB SNR margin, or does it have to reset over time by itself?
Thanks
Derek