When you freeze Avocados the frozen Avocados do last longer when frozen because the freezer keeps any bacteria from growing on the Avocados.
But when you freeze Avocados the texture and taste changes a bit once you thaw the frozen Avocados out.
Still frozen Avocados can safely be eaten like they are if you want too or you can use the frozen Avocados for making things such as guacamole, dressings and spreads.
I stock up on some Avocados on sale and then freeze them until ready to use and I've found that frozen Avocados last for a year or two before going bad.
I usually use the frozen Avocados within a year or less though but sometimes I have some leftover frozen for 2 years and they've still been good to make things with.