I think the general idea to prevent it getting ugly in courts is for landlord to be open to any lease ending early, but being clear they need to be kept whole for what they would have received for rent had the term not been terminated early. The law is very clear, if the tenancy ends early, the landlord must attempt to re-rent, and only when it is re-rented can the damages be quantified. The problem as always is enforcement of judgement and tenants being reasonable. I dealt with this last year and was left holding the bag as they just walked away, trashed the place and was a total mess paying the bills.
"I believe that banking institutions are more dangerous to our liberties than standing armies. If the American people ever allow private banks to control the issue of their currency, first by inflation, then by deflation, the banks and corporations that will grow up around the banks will deprive the people of all property until their children wake-up homeless on the continent their fathers conquered."
-Thomas Jefferson 1802