Unbound crash with fatal error - error_supers: assertion 0 failed

Running Windows 10/65 v1803 b17134.137

I have included salient bits from the log which starts as you can see at 12:38 and all is working just fine until 17:17 apart from the bits I have included below. There are quite a few:

“event_add failed. in cpsl.” (more than I have included)

07/07/2018 12:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] notice: init module 0: validator

07/07/2018 12:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] notice: init module 1: iterator

07/07/2018 12:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: start of service (unbound 1.7.3).

07/07/2018 12:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] notice: sendto failed: Network is unreachable.

07/07/2018 12:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] notice: remote address is 202.12.27.33 port 53

07/07/2018 12:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] notice: sendto failed: Network is unreachable.

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07/07/2018 12:28:15 C:\Program Files\Unbound\unbound.exe[1856:0] error: event_add failed. in cpsl.

07/07/2018 12:28:15 C:\Program Files\Unbound\unbound.exe[1856:0] error: event_add failed. in cpsl.

07/07/2018 12:28:15 C:\Program Files\Unbound\unbound.exe[1856:0] error: event_add failed. in cpsl.

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07/07/2018 12:37:56 C:\Program Files\Unbound\unbound.exe[1856:0] error: event_add failed. in cpsl.

07/07/2018 12:37:56 C:\Program Files\Unbound\unbound.exe[1856:0] error: event_add failed. in cpsl.

07/07/2018 12:37:56 C:\Program Files\Unbound\unbound.exe[1856:0] error: event_add failed. in cpsl.

07/07/2018 13:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: server stats for thread 0: 1490 queries, 723 answers from cache, 767 recursions, 13 prefetch, 0 rejected by ip ratelimiting

07/07/2018 13:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: server stats for thread 0: requestlist max 182 avg 16.6795 exceeded 0 jostled 0

07/07/2018 13:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: average recursion processing time 0.220371 sec

07/07/2018 13:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: histogram of recursion processing times

07/07/2018 13:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: [25%]=0.0387571 median[50%]=0.104983 [75%]=0.29279

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Then its all fairly quiet until:

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: server stats for thread 0: 3758 queries, 2062 answers from cache, 1696 recursions, 88 prefetch, 0 rejected by ip ratelimiting

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: server stats for thread 0: requestlist max 182 avg 11.0936 exceeded 0 jostled 0

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: average recursion processing time 0.186127 sec

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: histogram of recursion processing times

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: [25%]=0.0234981 median[50%]=0.0849854 [75%]=0.245

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: lower(secs) upper(secs) recursions

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: 0.000000 0.000001 236

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: 0.000512 0.001024 1

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: 0.001024 0.002048 2

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: 0.002048 0.004096 10

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: 0.004096 0.008192 12

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: 0.008192 0.016384 97

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: 0.016384 0.032768 152

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: 0.032768 0.065536 246

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: 0.065536 0.131072 310

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: 0.131072 0.262144 237

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: 0.262144 0.524288 245

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: 0.524288 1.000000 112

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: 1.000000 2.000000 28

07/07/2018 16:28:13 C:\Program Files\Unbound\unbound.exe[1856:0] info: 2.000000 4.000000 8

07/07/2018 16:29:14 C:\Program Files\Unbound\unbound.exe[1856:0] error: can’t bind socket: Permission denied. for 0.0.0.0

07/07/2018 16:33:17 C:\Program Files\Unbound\unbound.exe[1856:0] error: can’t bind socket: Permission denied. for 0.0.0.0

07/07/2018 16:33:33 C:\Program Files\Unbound\unbound.exe[1856:0] error: can’t bind socket: Permission denied. for 0.0.0.0

07/07/2018 16:35:36 C:\Program Files\Unbound\unbound.exe[1856:0] error: can’t bind socket: Permission denied. for 0.0.0.0

07/07/2018 16:36:16 C:\Program Files\Unbound\unbound.exe[1856:0] error: can’t bind socket: Permission denied. for 0.0.0.0

07/07/2018 16:54:23 C:\Program Files\Unbound\unbound.exe[1856:0] error: can’t bind socket: Permission denied. for 0.0.0.0

07/07/2018 17:05:14 C:\Program Files\Unbound\unbound.exe[1856:0] error: can’t bind socket: Permission denied. for 0.0.0.0

07/07/2018 17:06:27 C:\Program Files\Unbound\unbound.exe[1856:0] error: can’t bind socket: Permission denied. for 0.0.0.0

07/07/2018 17:14:53 C:\Program Files\Unbound\unbound.exe[1856:0] error: can’t bind socket: Permission denied. for ::

07/07/2018 17:17:29 C:\Program Files\Unbound\unbound.exe[1856:0] fatal error: iterator/iterator.c:237: error_supers: assertion 0 failed