you are in VM,s loop - there is no guarantee it will happen on the 19th - thats most likely just a date plucked out of the air - it might happen - it might not but the one thing that is sure is VM have absolutly no idea - staff on here will make all the right noises and can do nothing but refer it up the chain - those that its rferred to will again do nothing
you need to sort this in the short term with an alternative - 3 on their network or back to your old isp on a 30 day rolling contract - then wait for VM to install and get all the compensation you are due - they [VM] are likely to try and rob you of what you are due but keep notes and go to arbitration if needed adding a £100 or so for the way you are being messed about