So around the time the cryptocurrencies reached all-time highs earlier in June, with the Bitcoin price hitting $3,000 and Ethereum breaking $400 the following day, Novogratz thought the current crypto boom had topped out. He sold “a bunch” of his digital coins.

“I think the market had a spectacular run, and trees don’t grow to the sky,” Novogratz said this week, speaking at CBInsights’ Future of Fintech conference in New York. “So I probably still have roughly 10% of my net worth in crypto, but it’s been scaled way back.”

“I own a lot less coins, they’re just worth more,” Novogratz added.

His call turned out to be well-timed. Just days after setting record prices, Bitcoin and Ethereum crashed as much as 25% in just 24 hours. Ethereum kept right on falling, at one point trading 46% off its high — and that’s not even counting last week’s flash crash in which the price briefly plummeted to just 10 cents.

Cryptocurrency traders have become accustomed to their prices violently whipsawing up and down in waves — a 30% drop in the Bitcoin price in May preceded its recent peak by about two weeks — but the current downdraft appears more sustained. Though the cryptocurrencies, rooted in a technology system known as the blockchain, have each since recovered some of their losses, they have yet to come anywhere close to their highs.

Now, Novogratz, who formerly ran a hedge fund at Fortress Investment Group and now invests in blockchain companies, thinks the cryptocurrencies have peaked for the time being, and it could be a while before they return to record levels. “I think we may have put the highs in for the year in Ethereum, and you’re going to slowly consolidate,” he said at the conference.

To be sure, the billionaire is still bullish on digital currency over the longer term — he’s just waiting for the right time to buy again. And he has a pretty good idea of when that is.

If Bitcoin fell back down to $1600, he said, he’d “be buying a lot of it.” And if the Ethereum price retreated to between $150 and $200, it would be cheap enough to merit buying more, he added.

Those prices would give Ethereum a total market value of about $20 billion, which “sounds about right for where we are” in the evolution of the technology, Novogratz said.

After all, even if you believe, as he does, that the cryptocurrencies have much further to run — he compares the current phase of the industry to the third inning of a baseball game — investors who bought in amid crescendoing hype have still gotten burned in the meantime. “If you buy Ether at $400 and it goes to $200, I don’t care what inning you think it is, it feels really shitty,” Novogratz said. “You’ve got to be pretty careful when you enter these things.”

(Lest anyone doubt the present frenzy among cryptocurrency traders, a popular Reddit thread points to a newly created website shouldisellmybitcoins.com, which generates a “No” response in the form of a different amusing Gif image each time anyone clicks on it.)

Eventually, however, Novogratz believes there will come a time when investors are better off getting out of cryptocurrency entirely — though it’s likely still a long way off. “I sense that this blockchain, Bitcoin, Ethereum, ICO revolution is going to be the single greatest bubble of our lifetime,” he predicted. Of course, when that bubble pops, it’s probably a perfect time to buy back in.