The fact that the FTTC is "the other side of our front garden wall" does not guarantee maximum speed.
The local FTTC here is probably a similar distance, about 10 Metres from my front door; but the link cables to the PCP travel about 50 Metres to the PCP, followed by about 250 M of original phone cabling, to get to my front door, still only 10 M from the FTTC.
(I can see inside the FTTC when opened, from my lounge window.)
I forget the site which gives forecast BB speeds; but when I used it to extract the forecast speeds for all 77 houses on this estate, it showed that my house and the others in the immediate group, were likely to get the slowest BB speed, whilst geographically the nearest to the FTTC; and second nearest geographically to the PCP.
The most remote houses on the estate, about 500 M from the PCP, are forecast to get faster speeds, although not maximum.
The estate was fully phone-wired during build on a greenfield site in 1967, so no obvious reason for the extended wiring.
So the geographic locations of the FTTC and of the PCP are not reliable indicators of likely Broadband performance.
In our case, I don't think it's that big an issue:
VDSL Training Status: Showtime
Mode: VDSL2 Annex B
VDSL Profile: Profile 17a
Traffic Type: PTM Mode
Link Uptime: 1 day: 1 hour: 30 minutes
VDSL Port Details Upstream Downstream
Line Rate: 20.202 Mbps 80.103 Mbps
Actual Net Data Rate: 20.000 Mbps 79.987 Mbps
Trellis Coding: ON ON
SNR Margin: 9.7 dB 12.9 dB
Actual Delay: 0 ms 0 ms
Transmit Power: -12.6 dBm -12.6 dBm
Receive Power: -16.2 dBm 5.9 dBm
Actual INP: 0.0 symbols 0.0 symbols
Total Attenuation: 0.0 dB 6.4 dB
Attainable Net Data Rate: 25.828 Mbps 105.494 Mbps