(Sorry about all the typos, ADHD problem). And the communication problem was that for gpsmon to communicate "with shared memory" correctly to chrony gpsmon need

(Sorry about all the typos, ADHD problem). And the communication problem was that for gpsmon to communicate "with shared memory" correctly to chrony gpsmon needs to start first. The default installation sets the order the other way around. At least it was my findings for me that the instructions in the article only worked because people tended to still leave network based time services in the chrony configuration. If you take these away it would not lock. In any case, fixing the start order made this problem go away so it must have something correct about it.