I am in a similar situation to you, right now in the process of finding out where the slow-spots and not-spots are. Like you our first plan is to contact BT. Did you sign up for http://www.communityfibre.bt.com/
? If not I would do so because I believe doing so is going to be used as a preregistration for any updates under the USO.
The USO is also demand-led, so groups of small properties will again also come last as they have for BDUK.
In the short term, do any of the 9 properties have line of sight view to any property which gets a good +50Mb/s FTTC connection? If so, install a second FTTC line to it and arrange a point to point wireless link to that property and one of the 9 houses, from there distribute that signal via fibre to the other 8 houses. When G.fast is available, in 5 years maybe, update that FTTC line to about 200Mb/s on G.fast, though BT might be able to supply fibre-on-demand to that property at a reasonable cost by then too. Update the point to point radio at that time if needed and maybe install a load balancer at the house which distributes the connection by fibre.
So you have to make a educated guess about what will be available in a few years time in 2020 and try to make sure that any investment you make now is not all thrown away whenever something else looks viable. Which is why I am saying connect the 9 houses via fibre now, so it would only be the point to point wireless link which will be upgraded in the future.
Do post any other thoughts or plans you have and what results you achieve. Also search youtube for 'uknof' and see what other people have done. There is no one right solution.
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