Cramer expects the analysts to upgrade Chipotle after it reports knowing that numbers will improve going forward. That is why Ackman had to move, Cramer said.
"I said to buy Chipotle at $400, and I reiterate that statement. If it comes closer to that level, I think you should join Bill Ackman and invest in the stock of this once great and soon to be great again restaurant chain," Cramer said.
Many investors will now focus on what Ackman will say to Chipotle's management. In addition to his new 9.9 percent stake in the company, he also will speak to Chipotle management about possible changes.
Ten years ago, Ackman tried to get McDonald's to re-franchise its stores to improve profit margins. Then five years ago, the managers at Brazil-based investment group 3G invited Ackman to be involved in taking Burger King private while adopting the re-franchising theory.
"I think that Ackman can certainly push for Chipotle to go to a franchise model from its wholly-owned structure, but that won't be received well as current management likes to keep tight control over its business," Cramer said.
Ultimately, Cramer says that buying Chipotle's stock right now is a bet that health scares are behind it.
The next quarter coming up will mark a year since Chipotle's health incidents, which tends to indicate a bottom based on the history seen with the other restaurant chains hit with health problems.
Investors aren't like a hedge fund manager like Ackman, so they have more flexibility. That is why Cramer advised to wait for Chipotle at $400.
"American people tend to forgive and forget. Soon Chipotle will be forgiven, the illnesses will be forgotten, and the stock will be ready to run, maybe not to the heights we saw before its 40 percent fall from grace, but certainly to levels that will make it worth betting on," Cramer said.