That's a pretty pessimistic timeline, if the injury is as reported. His spring preparation won't be done according to plan, but he should be ready to ride at Flanders at Roubaix.
His Spring preparation is now. Paris Roubaix is April 12th...just over 3 months away. That, and ask any rider that's completed a backmarker's pace what part of their body wasn't in agony. I believe the answer is none and the most affected parts are neck, hands, feet and lower back. Those areas take a beating, for sure.
He is a Trojan for pain endurance but not being able to train for that abuse is a limitation. That's why he does/did cyclocross.