NAVADMIN 065 released: 
https://www.public.navy.mil/bupers-npc/reference/messages/Documents/NAVADMINS/NAV2020/NAV20065.txt
In particular 3C for OCS/ODS and other training:
3.E.  NAVY RESERVE PERSONNEL WILL FOLLOW GUIDANCE PROMULGATED BY THE CHIEF OF 
NAVY RESERVES.
    3.C.  TRAVEL FOR OFFICIAL TRAINING.
          3.C.1.  SERVICE MEMBERS AND NAVY CIVILIANS TRAVELING TO ATTEND 
FORMAL TRAINING, TO INCLUDE ACCESSIONS TO RECRUIT TRAINING COMMAND OR OFFICER 
TRAINING COMMAND, AND WHO HAVE NOT YET INITIATED TRAVEL, WILL REQUIRE AN 
EXCEPTION IAW PARAGRAPH 3.E.
          3.C.2.  SERVICE MEMBERS AND NAVY CIVILIANS WHO HAVE ALREADY 
INITIATED TRAVEL FOR TRAINING ARE AUTHORIZED TO COMPLETE TRAINING, INCLUDING 
INTERMEDIATE STOPS, AND CONTINUE TO THEIR FINAL DESTINATION.
    3.D.  PERSONAL LEAVE AND LIBERTY FOR SERVICE MEMBERS.
COMMANDING OFFICERS AND OFFICERS IN CHARGE MAY AUTHORIZE LOCAL LEAVE IAW 
COMMAND POLICY.  LEAVE OR PERSONAL TRAVEL OUTSIDE OF THE LOCAL AREA, AS 
DEFINED BY COMMANDING OFFICERS AND OFFICERS IN CHARGE, REQUIRES AN EXCEPTION 
AS OUTLINED IN PARAGRAPH
3.E.  APPROVAL AUTHORITY FOR LEAVE REQUESTS INVOLVING TRAVEL OUTSIDE OF THE 
LOCAL AREA IS THE FIRST FLAG OFFICER OR SES IN THE CHAIN OF COMMAND, FOR BOTH 
UNIFORMED SERVICE MEMBERS AND NAVY CIVILIANS.  FOR THOSE MEMBERS CURRENTLY ON 
LEAVE, COMMANDING OFFICERS OR OFFICERS IN CHARGE ARE DELEGATED AUTHORITY TO 
TERMINATE LEAVE EARLY OR ALLOW COMPLETION OF LEAVE AS AUTHORIZED BASED ON 
LOCATION, DURATION AND RISK TO SERVICE MEMBER.
    3.E.  EXCEPTIONS.  COMMANDING OFFICERS AND OFFICERS IN CHARGE MAY REQUEST 
AN EXCEPTION TO PARAGRAPHS 3.A. THROUGH 3.D.
IN THE FOLLOWING CASES: (1) DETERMINED TO BE MISSION ESSENTIAL,
2) NECESSARY FOR HUMANITARIAN REASONS, OR (3) WARRANTED DUE TO
EXTREME HARDSHIP.     MISSION-ESSENTIAL TRAVEL REFERS TO WORK
THAT MUST BE PERFORMED TO ENSURE THE CONTINUED OPERATIONS OF MISSION 
ESSENTIAL FUNCTIONS, AS DETERMINED BY THE COMMANDING OFFICER OR OFFICER IN 
CHARGE.