If you are a member of the National Guard or Reserves, being called to active duty for more than 30 days makes you and your family eligible for TRICARE Prime and Standard the same day you are due to report. You are eligible for these plans until 180 days after you have returned from active duty.
Make sure that all of your DEERS information is kept up-to-date and that you have current military ID cards issued for all members of your family over the age of 10; while you can update DEERS after you have been mobilized, it is one less thing to worry about during what is sure to be a busy time for your family. You may also want to submit a DD Form 2870 for “Authorization for Disclosure of Medical or Dental Information” to your claims processor to allow your spouse to make inquiries about your TRICARE claims.
You can download a copy of DD Form 2870 here: https://www.hnfs.com/content/dam/hnfs/tn/common/pdf/auth_to_disclose_dd_2870.pdf