I think the town I live in is one of the largest in derbyshire but sitll no support.
At around 20,000 people Belper seems to be a bit borderline for unbundling.
Whilst there are many smaller exchanges (e.g. Brackley in Northamptonshire, which has around 15,000 people, has Sky/Easynet, BE/O2, Talk-Talk, AOL & Tiscali - more providers than our exchange which serves around 50,000 people!!!; but Brackley does have more business lines than your exchange) which have been unbundled by companies such as Sky/Easynet & BE/O2; there are many larger ones which haven't.
Possibly what's swinging the case against your exchange (and possibly county) is it seems whilst Derbyshire has two very large towns (Chesterfield & Derby) all other towns seem to be around 21,000 or smaller (so there may not be a huge amount of backbone capacity outside of the main two towns).
Also; Derbyshire is a very rural county (indicated by all the towns, except two, being quite small).
This is also shown by the relatively small number of business lines supplied by your exchange (4% of lines; compared to 6.2% for our exchange and 12.2% for Northampton - which is a large town with a lot of businesses).
Many LLU providers (especially Sky/Easynet and C&W) will likely concentrate on areas where they can sell their product to businesses.
It's also possible in addition to there being not much non-BT backbone, your exchange may not be big enough for much non-BT equipment (some exchanges, especially ones built since the 1980s, are just small sheds).
The fact your exchange was given a date by BE (even though it was withdrawn) shows it's on their watch list; so there may be hope for you.
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