I had a problem with my ADSL connection a few months back where it slowed down to virtually unusable speeds. (have splitter installed, new house).

A technician fixed something in the whisper cabinet and my sync speed went up to ~23,000kbps but after a few days it reduced to ~20,000kbps (my pre-fix speed too). 

Being a bit interested in this, I was wondering if it were possible to regain the 23,000kbps speed. 

This is the modem status page...

DSL Details
Modem Type: Built in modem - ADSL
DSL Line (Wire Pair): Line 1 (inner pair)
Current DSL Connection:
Down Up
Rate: 20957 kbs 921 kbs
Max Rate: 20957 kbs 960 kbs
Noise Margin: 12.0 dB 12.2 dB
Attenuation: 1.7 dB 0.8 dB
Output Power: 15.6 dBm 12.3 dBm

Protocol: G.DMT2+ Annex A
Channel: Fast
DSLAM Vendor Information Country: {46336} Vendor: {IKNS} Specific: {256 }
ATM PVC: 0/100

Rate Cap: 20957 kbs
Attenuation @ 300kHz: 0.4 dB
Uncanceled Echo: -20.3 dB Ok
VCXO Frequency Offset: -67.1 ppm Ok
Final Receive Gain: -10.7 dB Ok
Impulse Noise Comp. Tones: 0 Ok
Excessive Impulse Noise: 0 Ok

And this is the diagnostic page....
GENERAL
Downstream Rate Cap: 29552 kbps
Downstream Atten. at 300kHz: 0.4 dB
Impulse noise protection: 0.00
Delay of latency path:0.04 ms

I have read somewhere on this website that telecom can put you on different profiles and I asked them on the phone about this but they didn't know what I was talking about so no luck there. 

Is it possible to increase my speed based on the above connection stats?  Or, am I at max speed and the previous speed boost was due to some testing they were doing?