There may be a quicker
way.
There may be a mechanism by which the fabric of the Universe can be spontaneously rent, in the form of a collapse of probability functions of the particular quanta that make up our or any other local universe. This would "appear" as bubbles of total vacuum exploding continuously outward into the local space and devouring everything their wavefront crosses at the speed of light.
No warning. No escape.
Moving Wave of Cease-to-Be (+∞, +∞).