Most companies I've worked for were actually sub-leasing at some point, so it also isn't actually necessary to break the lease at all and could only have admini

Most companies I've worked for were actually sub-leasing at some point, so it also isn't actually necessary to break the lease at all and could only have administration costs as long as the rest of the market is maintaining the pretense that office space is going to stay valuable. That's actually a good reason to line up a sub-leaser with a contract early.