I know of a USMA plebe who outprocessed at the beginning of summer, and it took him about 2-3 weeks. I don’t have any personal experience with the process, but I have heard that part of the reason it takes so long is to make sure the cadet is making the right decision. They don’t want cadets to make a hasty decision about leaving, and therefore this process provides time to talk with various leadership and reconsider.
This is a good point. When I was on USNA Commandant’s staff, every mid who applied to leave voluntarily was seen by several members of the chain of command and a Chaplain, to ensure the mid was thinking clearly, not acting impulsively or didn’t have a problem that could be addressed with local resources.
Mids who came in to see me who were clearly running TO something concrete, not AWAY from something, could articulate a plan, had talked it through with family and mentors, and seemed relaxed and settled in their decision, made for a quick 15 minutes and best wishes from me.
Others took way longer to get at the root of what was going on. One youngster, a star varsity sprinter with negative whatever body fat, struggled with swimming quals to the point he didn’t want to deal with it and just wanted to never see a pool again he had to do mandatory things in. Pride was a big factor too. I called a SEAL I knew on staff, asked if he was willing to help, called the head of ProDev to see if we could wiggle the mid’s summer training schedule around, called over to the Midshipman Development Center about counseling, called the head track coach and got him onboard to excuse him from off-season running routine temporarily (that coach or an assistant regularly dropped by the pool to support him during his 1:1 SEAL swim sessions), got the Dant and DepDant buy-in, and we set him up with a 3-week custom training block, where he had 1:1 swim coaching for tech skills and performance counseling to get over his ingrained fears. The SEAL taught him how to leverage his enormous lung capacity and stamina to remain buoyant and the mechanics to take advantage of his natural athleticism. He completed every swim qual required for graduation and never went near a pool again. Went Marine ground. Proudly graduated and learned a lesson about pride.
For the OP, the moral of my sea story is if you are clear and settled about leaving and have your plan (which it seems like you do, given school registration), be articulate and confident in your plan. If part of you wants to stay, ask for help. Give careful though to maximizing your free academic credits you can take away. Can you bear to complete the entire year, a day at a time? Rhetorical.
Just be sure you are running TO and not AWAY.