Last year's start was unprecedented, and the pit lane isn't wide enough to accommodate that many bikes in a race start - none of them are that big, they'd have needed an entire grid marking out. As the entire field aside from JM43 changed, they re-formed in their qualifying order behind where the back row was. It wasn't ideal, but better than the carnage that would have ensued had 26-odd bikes tried starting in a mass melée from pit lane. Race Control and the Safety Commission had no choice but to improvise.
MM93 got a ride-through penalty for his self-start and re-position on the grid last year - actually I thought he did very well, but unfortunately it was all illegal...