Can leadership force me to attend blc when I’m getting out?

Pro tip: Every question that starts with "can leadership force me to", the answer will most always be yes.
You're in the Army until you ETS. Your commander is expected to train his Soldiers.
BLC has a six month time in service remaining requirement, and you are CPL with more than 12 months remaining today, sitting in a SGT duty position without BLC complete, so yes, your unit is responsible for sending you to BLC.

That said, it sounds like your unit and some other E4 would be better off if you lateraled back to SPC, and someone willing to lead took that seat, that's commander's discretion, advised by the 1SG.

However, whatever you do in the private sector, you will most likely end up in charge of a few people and some point, and responsible for providing them with purpose, direction and motivation.
BLC is a place where you can learn some new perspectives and TTPs about that, from both the cadre and the other students. And its 3 weeks that you had to be doing something in the Army anyway, and odds are you've already learned everything you were going to learn sitting around your unit.

How many years do you have in the military? Why not try to stick it out for a good retirement that you can get after 20 years.

Explain your intentions to your leadership and chain of command about not re-enlisting upon your ETS date and that it would be a waste to send you over someone else who wants to go and is not planning on getting out. Some commands may still try to send you for one reason or another and if that happens you have 2 choices...go to the school and graduate or go to the school and fail out on something simple like failing the p.t. test. If you fail out they cannot send you back to the school for a set amount of time, I cannot remember exactly how long that is. By that time though, you will be within your ETS window and they won’t send you back.

Time for some hard lessons mentoring.

CPL (Join to see), you are a Corporal. You ARE an NCO. BLC gets you to be a higher ranking NCO. With that, I have to ask....Why did you accept the CPL stripes? Clearly your leadership saw potential in you IOT give you those stripes and that leadership role. Right now you say you don't have the drive. Who knows? Perhaps BLC will reignite that fire. Besides, it's good training. It's good knowledge. AND.....you can take that training and knowledge and pass it on to the other young Soldiers that are up and coming and will look to you for that information come their turn. Personally, I say give it a go.

That being said....now for the other side of the coin that is probably going to hurt your feelings.

You are a Soldier and an NCO. Pull up your panties and start acting like it. Muscle up, buttercup. If you feel that going to BLC and becoming a SGT will do more harm than good, then you don't deserve to be a CPL and need to tell your 1SG and CDR that you don't deserve those stripes nor the honor of leading Soldiers and to get the sham shield back. You have Soldiers that depend on you and your leadership. If you really feel that becoming a SGT will do more harm than good....then get the f*ck out of that leadership position and stop impersonating an NCO. Then, once you turn in your CPL stripes, you need to apologize to your Soldiers for failing them.

In my opinion never turn down and leadership education school even if you are planning to get out. I highly recommend attending any training you can get that will have some effect even as a civilian should you get out or change your mind last minute. From personal experience I had. Avery bad FTA attitude due to piss poor leadership when I made SP4 back in the day. My 1SG selected me to attend PNCOC then 6 months later BNCOC. I had all the plans in the world to get out but just prior to my ETS date we had a change in leadership and mission and I decided to stay. In short don't close any doors or burn any bridges just in case things change. If you still want to get out you will at least get some good training atet can be adapted to leadership on the outside. I have seen more than one Soldier sabotage everything on their way out only to have a change of heart and be told goodbye. I would stress thinking this out long term regardless of your plans.

CPL Lucas the reason you are selected to go to BLC is that you are fully qualified to attend. The unit will send you to meet readiness and educational requirements established by the Army. They can not deny you from going to that school unless you are flagged. This course is the first one of many inside the Non Comissioned Officer Education system. I will recommend that you attend and do your best while at it. A full year ahead many things can change. If you are fully committed on getting out and already on the path to attend and complete your Soldier For Life requirements then the unit can assign another Soldier to take your place. However, if you haven't even registered for your SFL TAP classes in order to transition out of the Army then the unit still believes you are thinking a possible extension or reenlistment. Even if is changing your MOS which I highly advise, you can continue your service in the Military. It appears that you lost the fire inside your MOS why not give yourself the chance to serve in another MOS, stay competitive and keep up that fire burning while having fun. All of this said assuming you have been a top performer within your MOS and not flagged at this time you have a great opportunity to continue service however, if you are flagged and not a top performer go see your Soldier for Life counselor to start your transition. Either way you plan to continue please do not leave without a solid transition plan. I have seen the good and the ugly of Soldiers leaving the Army without a plan and the struggle of not knowing what to do when they get out of the service.

Check it out you may find need of it later

I know it doesn't seem appealing but as mentioned plenty of times, as a CPL you should be going to refine your skills as an already NCO. If you're getting out, use it also as an opportunity to pick up some or enhance your leadership skills to prepare yourself for your life As a civilian. I actually learned more about leadership at BLC than I did ALC. Take advantage of that

Simple answer, of course they can make you go. This may be an opportunity to find your drive. What is the worst that can happen? Just go and make the most of it.

If you've given up, and are a detriment to others' progression then your first line should be pursuing a reduction board or bar to continued service for you. If they are honest in their assessment of your potential and are recommending you for BLC then you're doing something right. It may however be STEP related, which is to say they are mandated to send you. Either way, a resume from a SGT is more impressive than a resume from a specialist. And you never know if you'll go to retention or join the ARNG or Reserve last minute. Give yourself the best opportunity for future success.