+09Jan23=======================================================================
+1. Finish implemention of DXCIDR ip address filtering. This works on both
+ logins (treated the same as locked out - i.e. just disconnected) and also
+ with PC61s where these sentences are just dropped. Also attempt to prevent
+ any *following* PC11s with the same data getting through.
+2. Recognise PC18s coming from CC Clusters more nicely.
04Jan23=======================================================================
1. Fillout DXCIDR, attach checks in PC61 and logins. Login that fail will
simply disconnect, like locked out callsigns