Gamma-ray bursts [1] are a class of observations, not single event. Some of them may originate from relativistic jets [2] emitted by massive, spinning, charged objects colliding (e.g. black holes). Those jets' intensity is not uniform; if it's pointed at the Earth, that's worse than if it's pointed perpendicularly to it.
There are other mechanisms proposed that columnate the emission [3][4]. These involve a star's rotation creating a radiating column along the star's axis. (I'm not sure if the atoms in that column radiate with a bias.)
[1] https://en.wikipedia.org/wiki/Gamma-ray_burst
[2] https://en.wikipedia.org/wiki/Astrophysical_jet
Many stellar objects rotate and/or have a magnetic field, and thus an "up", "down", and "side" in spite of being a sphere. Pulsars (extinguished stars that emit radio waves from their poles) are another famous example.
Work to shed our biology faster.
We'll get to that sometime in the next hundred years or so.
Either way, it's not likely to produce a GRB in the first place, it's too far away to really affect the earth in dramatic sci-fi story ways, and it's pointed in the wrong way.
It's a "GRB candidate" in the same way you're a "lottery winner candidate" if you buy a ticket.