Ordinarily, you are responsible for the rent and other damages for the duration of the lease, thus for another 12 months. If you walk away from the apartment and don't pay rent, the landlord can sue you for those 12 months of unpaid rent. But, the landlord does have to make an effort to re-rent the apartment, thereby mitigating his loss. Hypothetically speaking, that might mean that you are stuck with two months rent, assuming that it is fairly easy to re-rent the unit. You would also be liable for his expenses (including advertising and legal, also lost rent in case the unit had to be re-rented at a lower rate). Leases sometimes have a "liquidated damages" clause, saying that for a flat fee, the landlord may agree to terminate the lease. If you pay the termination fee, that might be cheaper and much easier (and better credit history-wise) that disappearing and having him sue you for actually breaking the lease.
It is almost certainly required in the lease, if there is an early termination clause, that you have to get the landlord's consent. The "lease break charge" is presumably the liquidated damages for early termination clause, and you don't actually "break" the lease. The problem with your unofficial plan is that if the other guy just takes off without paying, you will be stuck with a lawsuit and end up paying more money than you planned.