Can an AD 2LT change branches prior to BOLC?

Im no officer, but im MI, and can tell you that if you branch detail, you are well behind your peers when you make CPT and are going to be completely lost when you take an S2. Branch detailed MI officers are literally the worst MI officers I’ve ever worked with

You can not change your branch once HRC has given it to you. The branching process is based on the needs of the Army and solely preference. You will be eligible to submit a packet for the Voluntary Transfer Incentive Program (VTIP). The tries to align their projected needs against their current strength. If the Army has too many MI officers and needs Infantry Officers in a certain your group you can request to transfer. They adjust the "In/Out" chart twice a year. That is the only mechanism in the Army to change your branch. You can go to the HRC website to look into it. There are also various requirements for the positions you can transfer into.

I have never heard of nor seen anyone change Branches after being assigned after commissioning. Usually, your first chance will be when you are getting close promote to Captain. Then you can Branch Transfer by taking that Branch's Advanced Course, or I believe it is CCC now.