I can't see the contracts from where I'm sitting, so I'm not in a position to tell you if the new leases were subleases or if they are entirely new leases that end the prior leases. You can figure out if a contract is going to let you "out of the old contract" by reading a contract before you sign it.
If you chose to sublease your apartment while taking over the lease on a different apartment, then you have legally obligated yourself to pay the rent for both apartments.
Read the contracts and let us know what they say.

