I called VM mobile last week, 11/11/16, and after 25 minutes on the phone, they sold me a new 4G SIMO package, which required a new SIM. My current SIM is 3G. I got an email the same day informing me the SIM was on its way.
The SIM has not arrived, I phoned this morning, the lady told me that the SIMO plan I was sold does not exist, hence the reason for its non delivery.
I spent 25+ mins on the phone last week, and was reassured several times that the plan was 4G and the deal was robust. The lady on the phoned tried to escalate it to the contracts team, who rejected her call. They seem uninterested in resolving the issue despite my being a VM mobile customer for 10+ years and a Virgin Media customer (in all its forms) for 17 years.
I am desperately dissatisfied to wait a week for a new SIM and a new plan, to phone up and be told it's not coming and the deal you signed up for (and they confirmed), doesn't even exist.
I'm very sorry to hear about your experience changing to a 4G package. I would like to take a closer look at your account to see if I can clarify the situation. I've sent you a private message which you can view by clicking on the envelope in the top right.