But Airbnb would seem to fit the portrait of a company that needs to raise cash, and wants to go public sooner rather than later as it faces the pressure of former and current employees with expiring stock options. Ackman said Pershing could do a deal and resolve governance issues within 30 days of doing due diligence and getting access to inside information, and could take a company public 45-60 days after that. On the other hand, he said, Airbnb seems to be favoring a traditional initial public offering over a SPAC, but with an IPO, Airbnb wouldn't know with certainty how much money it would be raising until the final days of its road show.