Openplotter 3 headless beta 64 bit - network NTP broken with AP setting?

[Paul M]

Using ntpq -p on a fresh install (two wifi interfaces, both configured to access my home wifi) gives:
ntpq -p
remote refid st t when poll reach delay offset jitter
==============================================================================
0.debian.pool.n .POOL. 16 p - 64 0 0.000 +0.000 0.000
1.debian.pool.n .POOL. 16 p - 64 0 0.000 +0.000 0.000
2.debian.pool.n .POOL. 16 p - 64 0 0.000 +0.000 0.000
3.debian.pool.n .POOL. 16 p - 64 0 0.000 +0.000 0.000
#main.macht.org 124.216.164.14 2 u 4 64 37 29.916 -0.229 14.570
+ntp3.wirehive.n 202.70.69.81 2 u 3 64 37 10.719 -3.122 4.485
#101.100.146.146 202.46.177.18 2 u 67 64 17 276.246 +0.036 2.293
+time.cloudflare 10.19.9.88 3 u 63 64 17 14.949 -2.849 22.630
+gowest.hojmark. 193.67.79.202 2 u 64 64 17 16.106 -3.267 17.311
+time.shf.uk.as4 81.21.76.27 3 u 1 64 37 10.231 -4.604 2.749
+time-uk.tomhek. 85.199.214.98 2 u 61 64 17 14.550 -2.160 23.142
-ams.aput.net 131.176.107.13 2 u 63 64 17 17.190 -9.235 11.515
#send.mx.cdnetwo 125.185.190.74 2 u 4 64 37 263.019 -2.151 16.318
#ip-103-106-65-2 202.46.185.18 2 u 2 64 37 305.900 -5.842 14.552
+fluffykins.posi 178.62.68.79 3 u 2 64 37 9.279 -3.966 15.657
#bandersnatch.ro 193.79.237.14 2 u 3 64 37 16.785 -0.463 24.231
*185.83.169.27 .GPS. 1 u 6 64 37 19.681 -3.893 11.804
#ntp1.wirehive.n 202.70.69.81 2 u 11 64 37 12.007 +11.581 21.038
t+server1b.meinbe 79.133.44.146 2 u 13 64 37 28.368 -3.801 11.411
+ntp1.noris.net 96.160.39.195 2 u 16 64 37 27.218 -6.117 12.835

Running ntpq -p again after configuring AP mode in openplotter-network (and the re-boot)

pi@openplotter:~ $ ntpq -p
remote refid st t when poll reach delay offset jitter
==============================================================================
vodafone.broadb 193.79.237.14 3 u 12 64 1 0.969 +37953. 0.381

The clock increments but is not synchronised.

Disabling AP mode, rebooting and running ntpq -p again:

ntpq -p
remote refid st t when poll reach delay offset jitter
==============================================================================
vodafone.broadb 193.79.237.14 3 u 12 64 1 0.969 +37953. 0.381

clock is still not synchronised

running 'sudo dpkg-reconfigure ntp' gives no change in the ntpq -p output and the clock remains unsynchronised.

I'm a little out of my depth so I'm not sure if the above is at all relevant?

Paul