We know that most of the altcoins are moving the same as how Bitcoin's price is. Bitcoin is up = Most altcoins up as well, and vice versa.
Basing on history, I think it would be better if you buy altcoins months before the halving happens, or months after the halving happens because during the last halving, nothing significant happened, and the price of Bitcoin didn't go up a few weeks after the event happened.
Overall, it would always be better if you buy altcoins during the bear market, but if you don't have money at that time (which is a bit unfortunate because that's what I consider the best time to accumulate altcoins), buy altcoins a few months before the halving, or a few months after the wedding, but prices of altcoins went up already at that time like what's happening right now.