8 months. I have just received a very informative email from the head of the superfast broadband team at BT. Good explanation, just wish I didn't have to dig so deep for it... See below.
Ian Livingston forwarded me your email correspondence as I run BT's superfast broadband programme. BT Retail's < 15Mbps product will be available for customers in April. I am sorry it is not available to you now and I recognise you have been told of its existence, but BT Retail have not marketed the product externally. They have just completed their trials and are now in their final preparations for customer launch.
I can categorically assure you that BT Retail are not avoiding selling a < 15Mbps fibre product because of the impact on any speed charts. In fact, this could not be further from the truth. It is so that BT Retail can be as open and honest with all customers about what their line will be able to achieve from Openreach's fibre-to-the-cabinet technology. Other ISPs have chosen to combine Openreach's > 15Mbps and < 15Mbps product variants into one fibre product - BT Retail have chosen to distinguish between them; hence BT Infinity as a > 15Mbps product and the new < 15Mbps product to be launched in April.
With regard to the Welcome to Infinity letters, I apologise if you feel you have received one incorrectly. For regulatory reasons, BT Retail cannot line check every customer in an area that Openreach has enabled with superfast broadband unless the customer is an existing BT Retail Total Broadband or PSTN customer. BT Retail customers whose lines get < 15Mbps should not have been sent a Welcome to Infinity letter.
Once again, I'm sorry you cannot get a < 15Mbps product from BT Retail now; but it is only a few weeks away.