The bad news is no, we have nothing even remotely close to the infrastructure necessary to move half the world's population. We don't have the transport, being limited to planes and boats mostly.
The good news is that, worst-case scenario, this is going to wipe out a city. And cities and their surrounding areas can absolutely be evacuated. We definitely have the cars and buses necessary for that.
But in any case, we certainly have the logistics to move populations given the timeline. Not everyone has to evacuate and return within a 3 day window.
Even without incentives, in all likelihood, those who can will evacuate early for peace of mind, and as the prediction becomes more certain on its approach through measurement, individuals will I'm sure even start to return /before/ the pass. You know everyone has their own set of 9s to chase
Even if we had three years to move everyone from one side of the earth to the other and could handle the transportation, and then another three years to move them back, how are you going to keep them fed? We're just going to double our food infrastructure on half of the world?
Where do we house them for several years? We're going to double our housing?
How are we going to find all those people jobs to sustain them for the several years they're spending on the other side of the world?
All those things would have to be part of the logistics too. Energy usage. Health care. The list goes on.
It would be a logistical and economic upheaval the likes of which the world has never seen. It would lead to political chaos and massive wars over suddenly incredibly limited resources.
Humanity would survive, but a lot of people wouldn't. It wouldn't be a question of logistics, but a complete and increasingly violent reconfiguration of society in all spheres.
The good news is that, worst-case scenario, this is going to wipe out a city. And cities and their surrounding areas can absolutely be evacuated. We definitely have the cars and buses necessary for that.