http://www.berklix.com/~jhs/src/bsd/fixes/FreeBSD/src/gen/etc/services.ups-nut.REL=CURRENT.diff
By { 12.0-ALPHA8 & 12.1-RELEASE & 2018-11-06 13.0-CURRENT } 
etc/services had moved to usr.sbin/services_mkdb/services

# *** 13.0-CURRENT/src/usr.sbin/services_mkdb/services	Tue Nov 25 03:59:29 2008
# --- new/src/usr.sbin/services_mkdb/services	Sun Nov 11 22:28:35 CET 2018
# ***************
# *** 2190,2195 ****
# --- 2209,2216 ----
#   iscsi-target	3260/udp   # iSCSI port
#   ccmail		3264/tcp   #cc:mail/lotus
#   ccmail		3264/udp   #cc:mail/lotus
# + ups-nut		3305/udp   #UPS power local/share/doc/nut/README < ports/sysutils/nut
# + ups-nut		3305/tcp   #UPS power local/share/doc/nut/README < ports/sysutils/nut
#   mysql		3306/tcp   #MySQL
#   mysql		3306/udp   #MySQL
#   dec-notes	3333/tcp   #DEC Notes

*** 13.0-CURRENT/src/usr.sbin/services_mkdb/services	Wed Mar 11 10:37:18 2020
--- new/src/usr.sbin/services_mkdb/services	Mon Mar 16 01:26:40 2020
***************
*** 1815,1820 ****
--- 1815,1822 ----
  iscsi-target	3260/udp   # iSCSI port
  ccmail		3264/tcp   #cc:mail/lotus
  ccmail		3264/udp   #cc:mail/lotus
+ ups-nut		3305/udp   #UPS power local/share/doc/nut/README < ports/sysutils/nut
+ ups-nut		3305/tcp   #UPS power local/share/doc/nut/README < ports/sysutils/nut
  mysql		3306/tcp   #MySQL
  mysql		3306/udp   #MySQL
  dec-notes	3333/tcp   #DEC Notes