First you can't see anyone as eligible until 21 days out since that's the calendar window.So my question is, do I need to do something, or when we get to Jan. 3 will we automatically be able to book for our onsite stay that starts Jan. 10?
Next your tickets start before your actual reservation so different rules apply for different dates. For now since your tickets start on January 5th you can only purchase 3 days in advance for your lenght of tickets or up to 14 days. That is what you are seeing today.
Once you get to Jan. 3rd you should you should be able to book for Jan. 10th for up to 14 days. You can't book for January 8-9 before Saturday January 5th.
Does that make sense?
Dave