if you bought altcoins last month it was the right time, because altcoins are in a good position now. last month bitcoin was still on the bottom, and now it's on top. In my opinion, it's better to take bitcoin, ethereum, BNB coins that are certain and have a small risk, not too big like shitcoin baby doge
Altcoins are bleeding as we speak, I think there is no good bad time to buy altcoins right now, we really can't confirm if bitcoin has already hit the bottom or it's just getting started but with DCA there shouldn't be any problem unless you have a short term goal, some new altcoins will be coming and they will be better than past top projects in 2021, do your own research.