Help - Infinity stuck at 22mbps since install

Question

Hello,
I had Infinity 1 installed on 16 November, expecting to achieve around 35.8mbps. Since install it has been stuck at 22mbps (+/-0.5mbps) according the the BT wholesale checker - my IP profile has never moved from this same speed. Uploading is running at 7mbps, which is exactly what I expected.
My install by MJ Quinn was very rushed and the engineer was frustrated throughout (complaining about a scheduling mix-up by BT). He was here less than 10 minutes, tested the BBC website connected and then left. A week later, we realised we had no dial tone and raised a fault. On 29 November an Openreach engineer turned up unexpectedly, stating he'd corrected some crossed-over wiring at the cabinet and we had our dial tone back.
I had hoped this error might have been the cause of my slow download speed and that it would increase over the next few days. Unfortunately it hasn't changed at all, but the fact that the MJ Quinn guy appears to have caused at least one fault makes me wonder if something else is amiss with the install or my line settings.
So far online and over-the-phone chatting to BT has been an exercise in frustration. I've been asked the most basic questions over and over and have patiently answered, hoping to be escalated to someone that appears to have any amount of technical knowledge. That hasn't happened - hence this post, in the hope that a moderator or someone else with expertise can help me out.

Answer 1

Obviously from that you would appear to be on the FTTC range B where as you were expecting to be on Range A. From what I can gather range B is given when the line quality is not as good and may have "A bridge tap" 
This happens when one cable is spliced into another to break out cable pairs that will appear in more than one location but it usually causes attenuation and raises the impedance of the line. In laymans terms - Gives slower speeds.
I don't think there will be anything you will be able to do about this. BT will say that you are within the estimated speed band and there is nothing to be done.
It could still rise if the drop in speed has been caused by DLM (Dynamic Line Management) lowering your speeds because of the initial poor install. If it is because of this it could rise over the  next few weeks. All you can do is wait and see.
Other forum members may be able to suggest something else.