As you have been given a high utilisation fault code you are entitled to compensation in the form of bill credits make sure you request this from a forum team member funny how they never mention this.
Also when you get a REVIEW date this is NOT a FIX date this is a date they give you to shut you up for a few months until they REVIEW it again and give you another REVIEW date.
High utilisation faults because Virgin Media over sold the broadband services in your are take YEARS not months to fix I have now waited 2 YEARS and 4 MONTHS and it's still no better and my current REVIEW is September 20th.
If you are in contract and have a long standing fault you are free to leave without penalty so if you want to switch providers do so unless you have loads of patience and don't mind waiting forever for an actual fix.
This is the poor quality of my Superhub 3 connection