The 29-year-old from New Zealand has dropped out of the March 7 event due to "undisclosed personal reasons," per ESPN's Ariel Helwani. Whittaker (20-5, nine knockouts) hasn't fought since losing to Israel Adesanya in October at UFC 243.
According to Helwani, UFC is working towards keeping Cannonier (12-4) on the fight card but doesn't have an opponent lined up. The main event of the evening features Weili Zhang (19-1) versus Joanna Jedrzejcyk (15-3) in a women's strawweight bout.
Whittaker is a two-time former UFC middleweight champion who first earned the title on an interim basis at UFC 213 before being promoted to undisputed champion after Georges St-Pierre vacated the title in December 2017 due to ulcerative colitis—the title is currently held by Adesanya.
At 6'0" and 185 lbs, Whittaker is trained in wrestling and boxing, while fighting as a striker rather than grappler.
There's also potential for welterweight/middleweight fighter Darren Till to make his return at UFC 248 with UFC president Dana White telling The Mac Life he's closing in a return (h/t Nolan King of MMA Junkie). That would seem to mostly be speculation at this point, but Till did post on Instagram teasing his return to the octagon in Las Vegas. He last fought in UFC 244 in November 2019, earning a split decision victory over Kelvin Gastelum.
In any case, a weak fight card has gotten weaker for UFC 248 and White will need to come up with something before the event comes to T-Mobile Arena in Las Vegas.