Your speed upgrade will be ready to take your connection from up to 50Mbps to up to 70Mbps. It's all thanks to DOCSIS® - the magic in our cables. Look out for it between January 2017 and January 2017.'
I haven't seen the 'between' dates quoting the same month before so perhaps you are about to be boosted ... Ooohhh Matron!
Over a period of 18 months my 'Your speed boost is on the way' got put back numerous times. When it did finally arrive I got an email informing me, but I still had to phone up VM because nobody had activated it at their end.
It was worth waiting for though and more recently the 70mbps config has been uprated to 80.5mbps without any fanfares. I get 76mbps during the daytime but it falls off a bit when the neighbours get home from school and work and switch on.