It has not yet been upgraded to FTTC, and appears from all the evidence to be scheduled for the FTTP on-demand trial, probably some time in the 2nd quarter next year
A bit of confusion there

.
The FTTP
fibre on demand trial applies purely to cabinets that already have FTTC at the time (or after) the trial starts. It will not be on non-fibred cabinets. Do you mean your cabinet is scheduled for true FTTP?
you say "No cabinet is both". Does that mean that when my cabinet is finally upgraded I will have a choice of either staying as I am or upgrading to the most expensive product by having FTTP installed, with no choice in between?
I'm not entirely sure what you are asking there.
As "products", a cabinet is or is not enabled for FTTC. That enablement consists of a second cabinet being installed close to and connected to it, with a direct fibre supply from the fibre headend exchange, which may not be the one the phone line is connected to.
The FTTP product is installed in the area served by a non-FTTC cabinet, but the cabinet itself is not upgraded. The spreadsheet data just presents it as cabinet enablement for simplicity. FTTH/P is what it says - fibre all the way with no intermediate conventional cabinets. There are of course various junctions and distribution points.
"Fibre on demand" is a hybrid system. That consists of fibre being run to the premises from the fibre cabinet associated with an FTTC-enabled cabinet.
In all cases, for a user to have a fibre type supply, FTTC/FTTP/On Demand, a change of product is required by the ISP, or of course a migration if desired. You can stay on ADSLx if you wish, or upgrade. You do not automatically get "fibre" when your postcode is enabled. The last time I looked, BT Retail fibre prices were pretty much the same as their ADSLx ones. The general premium with other ISPs seems to be about £10pm but with better allowances then their ADSLx products.
I'v got a page about it
here, but I've just given you the important bits, and that page needs updating for fibre on demand. (I'm a bit behind on updating a few pages

).
My broadband basic info/help site - www.robertos.me.uk
Domains,website and mail hosting - Tsohost.
Connection - Plusnet Extra Fibre (FTTC). Sync ~ 56.0/13.9Mbps @ 600m.
"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
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