From what I've seen most areas don't - they only ever released it for a relatively small number of areas (although those areas may well have covered a reasonably high percentage of population).
Not too sure that's the case. Numerous places I have checked across Cambridgeshire covered by the BDUK rollout, both cabinets in town centres, further out of towns, and villages/rural, are showing the 330 FTTPoD available on the line checker. It seems it is being included as part of the BDUK rollout here, where as previously enabled (commercial rollout) ones didn't and still don't show the option.
All of these have been new cabinets within the past 6 to 12 months and certainly not high population (compared with the places you may expect higher speed options to go up against rival providers)
Whilst I don't think it's likely, it'd be really nice to see that this "on demand" higher speed offering comes back in a few months with completely reworked pricing, far cheaper than currently. I suppose that's always a possibility (so as to prepare for that in coming months), even if it's workload/training that is being suggested as the current reason for the pause?
plusnet ADSL2+ Annex M (and previously Be* Jan 2009-Jan 2014, ZeN Dec 2006-Jan 2009, plusnet Aug 2004-Dec 2006, ZeN Apr 2003-Aug 2004)