Mark walks from a block-world to a presentist room

block-world--past, present, and future events all exist, like the parts of a spatially extended block

presentism--only things that exist in the present exist, and there is some notion of temporal becoming

Mark walks from a room described by a block-world into a room where presentism holds true. What, if anything, happens? 'When' does it happen? 

There are 3 cases:

case 1: time, outside of both rooms, is presentist

case 2: time, outside of both rooms, is block-world

case 3: neither case 1 nor case 2