In the description for the Portable Hole both "a rift to the Astral Plane" and "a gate to the Astral Plane" are mentioned. See the exert below (emphasis mine):
If a bag of holding is placed within a portable hole, a rift to the Astral Plane is torn in that place. Both the bag and the cloth are sucked into the void and forever lost. If a portable hole is placed within a bag of holding, it opens a gate to the Astral Plane. The hole, the bag, and any creatures within a 10-foot radius are drawn there, the portable hole and bag of holding being destroyed in the process.
What is the distinction between a rift and a gate to the astral plane?