What is the updated length allowed for paternity leave?

21 now.

I just had this discussion a couple months ago after my wife had our son. My unit saw the DOD directive and called HRC to get their guidance. HRC put out that it is still 10 days until they release an Army specific policy, they apparently felt that the DOD instruction was too vague. Nothing has been posted as of today. Check the S1 net on milsuite for the current updates.

I found this from an article from Jan 2018: https://www.navytimes.com/news/your-navy/2018/01/24/dod-paternity-leave-policy-still-up-in-the-air/

"In 2016, DoD asked Congress to approve an increase of paternity leave from 10 to 14 days. But in the law, which went into effect with the 2017 defense budget, Congress set the maximum number of allotted days at 21. For individual services to be able to put their own new policy in place, DoD must first set the standard."

This is on HRC's website: https://www.hrc.army.mil/content/Military%20Leaves%20and%20Passes%20AR%20600-8-10
Q12: How long is Parental Leave?

A12: A married Soldier on active duty whose spouse gives birth shall receive 10 days of non-chargeable parental leave (formerly called paternity leave) to be used in connection with the birth of the child. This absence must be taken consecutively and within 45 days following birth, or within 45 days after return from deployment. Active duty orders will not be extended to allow for parental leave. The 2017 National Defense Authorization Act has authorized changes to Parental Leave, but as of 1 January 2018 implementation guidance and implementation dates have not been provided to the Military Services, therefore the 10-day guidance still applies.