For the Army Accelerated OCS, how much time is the in-processing and what is the average time to go to BOLC after commissioning?

Are you doing State OCS or Federal "ft Benning" OCS? I commissioned through Federal OCS and the course took about 3 months. So for Federal OC, branching is based on OML/grade ranking and whoever was at the top of the OML got to pick first on whatever branches was available at that time. When I was in, the Guard and Reservist candidates attending the federal OCS already had their branches before starting and alot of the active duty soldiers really didn't like them since we "active duty" had to bust our butts to do well on the ftx and academic portions to score high in the OML whereas the guards/reservist hat to just "pass" since they already had their branches. Anyways, regarding Air Assault and or Airborne, you can only get those slots if your receiving unit is an airborne or air assault unit or if your sending unit has done a 4187 for you to do a follow on to those schools after your done with OCS. it has to do with "who's paying for it" You can try and get a walk on alot but it can be difficult.

When you say accelerated do you mean the one run by the National Guard or the Federal program at Fort Benning. Just want to clarify because some soldiers use those terms interchangeably but they’re two separate programs.

Congratulations, 2LT (Join to see)! I've been retired since MAY98 and went to OBC in 1974, so I'm afraid I can't answer your question for you.
However, I would like to know which RTI you'll be attending. Are you headed to the 200th Regiment (LDR) at Fort McClellan, AL?