Thank you, ***** ***** helps.
Ok, what you need to do is assign that lease from Shuttlecraft Inc to the new LLC. As long as there are no clauses in the lease that say that you can't assign, that shouldn't be a problem. This can be a very simple document, that simply states that all the relevant terms are stated in the lease, refer to it by date, address, signatories, etc. and then have it executed by the owners. That should allow you to have the lease govern your relationship between the LLC and the landlord.
If you want to leave 4 months before the lease ends, the best course of action is to communicate with the landlord first about this. A personal conversation is the best start, and just feel them out and see what they want to do. Maybe they are thrilled to get it back early and are willing to give you your deposit back. There is no harm in the discussion, because even if they know this is your hope, if you end up staying and paying rent those 4 months, they have no grounds to keep your deposit.
So give it a shot and see if you can get an agreement to release you from the lease and get back your deposit. If not, I would not simply leave if you want the deposit back. If you are willing to risk the deposit for the sake of not paying those 4 months, then that is an option, but do keep in mind that the landlord would have legal grounds to come after you for those 4 months due.
Let me know if you have any questions about this.