Adding to what I wrote here...
1st year is not just a shakedown of the ships but to help determine the crew to send to mars. Specialties needed for mars will also need to have a frontier settlement spirit and be able to handle the isolation. We need to see how tethering the two ships together for artificial gravity will work. Radiation mitigation will be a priority while not considered a show stopper. Everyone will understand and choose to take the risks.
2nd year getting supplies to go to mars is not an issue. We aren't going to get it right, but we will get enough of it right to go. We will fix things as we learn.
3rd year and 4th year. Getting supplies to mars will also qualify the vehicle for landing humans. Private industries are not the amateurs that the government elites actually are. Private industry will have dozens of tests landing where government thinks it's good to go on the second shot (or sometimes the first... those are the amateurs.)
5th year. We will first land half the researchers (perhaps 3 from each ship.) Not all the supplies on the ship will go to the surface (if much at all, we already have supplies directly sent to the surface.) The six or so on the surface will suggest what supplies from the ship (from as much diversity as we can provide) need to be brought to the surface. It may be the following year expeditions actually bring the rest of the supplies down. Eventually all researchers will be on the surface while the ships stay in orbit for future uses.
6th year. We have to wait for launch windows for the following researchers but can and should still send over supplies that don't have the same launch window restrictions.
7th year. We will now have a better idea of what kind of specialists are needed to figure out how to live on mars. We send lots of them. Landers may already be waiting in mars orbit sent there on lower cost trajectories. Mars is going to need labor. We need to make it possible for people besides the rich to go (there aren't enough rich to do the job.)
It's also important to get the right start. People that understand why ownership and the unenumerated rights our constitution talks about are important. Martians on the frontier should bring back that quaint idea that a persons word is their bond. Theft by 'consent' should be completely understood for the fallacy it is.