Apparently BCHCTL can quit working permanently:
":~$ bchctl getinfo
Post "https://localhost:8334": dial tcp [::1]:8334: connect: connection refused"
even if rpcuser/pass matches both .conf files
no firewall
":~$ ss -tuan"
reports 8334 is not being listened to by anything,
suggesting BCHD has simply abandoned the external control path
delete both .conf does not fix.