I understand exactly how frustrating this is, but it is not something we do deliberately nor have any control over.
HTC give us pretty much weekly shipping bills with product shipments due for landing in the UK both for new products and restocks of existing devices.
Unfortunately, the unreleased devices commonly have changes, which we then reflect as soon as we know on the site.
The choice is really to have "coming soon" pemanently on the site until they actually arrive, but this means customers have no idea at all whether that's three months (or a year for the Shift!) or due tomorrow.
The choice we made to put whatever date HTC have last told us is something we hope helps customers with as much as we know. It's annoying when dates slip, but better than no info at all. We find it's even worse when everyone finally gets a hard date and we have a waybill for the airport landing, only to find the plane got delayed due to weather or customs ahve picked that flight to examine. The weather ruined the launch of one device a few months ago when the whole UK was told delivery by midday Friday for customer shipments for Saturday AM, only for the delayed flight to finally touch down in Heathrow at nine o'clock that night!
Remember that our system for registering interest and notification is under no obligation for yourself to purchase from us, but is something we offer to try and make that sale to someone who is looking forward to the device painless and as soon as possible after stock arrives.
Kind Regards
Ivan