Everyone who get involved on crypto since 2017 already knows october - december will be always a good month for crypto, every year almost has same pattern. So i think in 2021 oct-dec will be another the best moment for crypto, so just buy now and enjoy the moon at december.
Hopefully what you say can be true this year even though I have seen market conditions very often at the end of every year, but for this year I can't make so many predictions because I only rely on a few references.
I have heard such things about December. It is said that something good or, vice versa, bad happens to crypto exactly in this month. But I don’t believe in the magic of months. For example, the growth of Bitcoin started in August in the previous year, so neither in October nor in December. On the other hand, we see that in the stock market there are New Year rallies in December, so maybe it has a connection with this as well.