VDSL signals operate over much higher frequency ranges, and therefore don't travel as far. The power is also controlled so it doesn't affect other lines too much, which is called power masking, and it's often the lower frequencies which have their power restricted so they don't affect adsl signals, and it's these lower frequencies which would normally travel the furthest if they had maximum power.

So it would appear that I am stuck with it and the only option will be to go back to ADSL

Probably. LTE is maybe an option for you, depending on the volumes of data you upload. Use the FTTC connection for downloads/streaming and LTE only for uploading big files which will reduce the quota you'll need to buy.

Does depend on 4G coverage though.

Even 3G would be better than his ADSL, but it does depend on signal strength.

Well the latest on this saga is that I decided to go back to ADSL as I was paying for something I could not get and then at 2am on the day I was due to go on to ADSL I had an email telling me that the change in upload speed that I requested has been implemented and I was now on 2mbs, it's actually 1.4 but that's double what I was getting before so the change is cancelled, no apologies, no explaination nothing.