Assigning a lease and/or terminating it

[dandelionseason]

So, my roommates and I want to assign our lease to some friends who are interested in our apartment. It's a lease that was automatically renewed last June 30th and will be renewed again this June 30th. We're worried that if our landlord rejects the new tenants we'll be stuck on the lease because the three month notice period will have expired (this is a last minute, friends want to take it over/keeping the rent down would be awesome thing, which is why I'm asking the day before the last possible day to give notice!) Can we give some sort of assignment of lease that also says we will be cancelling our lease if the landlord rejects our new tenants? Or do we just have to take a chance on him accepting our replacements?

Sorry if this is confusing! Thanks in advance if anyone has answers!