It's easier to understand if you look at it on a computer than a phone or ipad. Look at only one row at a time. Each oersin that is switching domicile has a "to" and a "from" box. If it's an upgrade, than it'll be from x domicile FO to x domicile CA. If it's FO to FO then they just switched base. If it's a new hire, it'll say "upon completion of training" under the effective date column.