In which case the only place you are likely to get an answer is the developer. Who may be reluctant.
For example, it is they who lay all the ducting and chambers for Openreach, before roads and pavements are surfaced and drives and gardens are laid.
If they won't be doing that it is unlikely Openreach would come along and dig everything up again. At least in the short term. I suppose long-term duct-sharing by companies such as Grain may be forced by government, as it supposedly is wrt existing OR ducts and poles.
Connections: OnePlus 8 Pro on Three 4+ (LTE)/5G and at home Three Mobile, with (Three)ZTE MF286D router giving about 113/20Mbps.
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The price of liberty, and even of common humanity, is eternal vigilance. (Aldous Huxley version of the well-known saying)
Were there none who were discontented with what they have, the world would never reach anything better. Florence Nightingale (Cassandra: an Essay (1860 edition?)