2.5+ years at the start of the breeding season. I know some people make it work with 1.5 at the start but the results usually aren't great. So like a 2020 you would have bad luck in 2022, but 2023 should be good.
Weight wise I will condition them for breeding at 1200g+, and they are almost always above 1500g by the time they are actually at the point of building that you should breed them. If they are a touch below 1500g, I'll still let them, but if they have a poor feeding response or any kind of health problem during conditioning then I won't.