Rsyslog default action name not sequential?

I would like to ask question about rsyslog.

I am using rsyslog v7 and gathering stats using impstats module. According to document, default naming of action queue is sequential based on occurrence of action inside rsyslog configuration.

name word

This names the action. The name is used for statistics gathering and documentation. If no name is given, one is dynamically generated based on the occurence of this action inside the rsyslog configuration. Actions are sequentially numbered from 1 to n.

However, after the definition of dynFile the action number jumps from 3 to 5

Sep 10 15:42:54 B rsyslogd-pstats: dynafile cache RemoteHost: requests=1427979 level0=871360 missed=57000 evicted=56990 maxused=10 
Sep 10 15:42:54 B rsyslogd-pstats: action 1: processed=1427979 failed=0 
Sep 10 15:42:54 B rsyslogd-pstats: dynafile cache Dashboard: requests=7018 level0=5941 missed=4 evicted=0 maxused=4 
Sep 10 15:42:54 B rsyslogd-pstats: action 2: processed=7018 failed=0 
Sep 10 15:42:54 B rsyslogd-pstats: action 3: processed=85295 failed=0 
Sep 10 15:42:54 B rsyslogd-pstats: action 5: processed=82487 failed=0 
Sep 10 15:42:54 B rsyslogd-pstats: action 7: processed=609 failed=0 
Sep 10 15:42:54 B rsyslogd-pstats: action 9: processed=832 failed=0

After action 3 , I use the forwarding rule using legacy format

:hostname, isequal, "BC" @BF
& ~

Is this numbering result natural behavior?