This response is provided based on the information you shared and should not be used as the sole source for making a decision. You should seek guidance from the chain of command, IG, JAG or other certified agencies before making any decisions. How you chose to use this information is totally up to you and is your sole responsibility.
If memory serves me correctly AR 600-20 only requires two policy letters: Open Door Policy and Equal Opportunity/Sexual Assault. There may be a requirement for Substance Abuse in AR 600-85 as well.
There are plenty of policies that are simply announced. Sending a message by text is not necessarily the best way to do it but it is a way they could chose to use.