The packages for the rides let you 'mix and match' what rides you go on, and have no time restriction on. For example, their roller coaster package gives you 5 Fastrack rides, and you can choose to do 1 ride on each coaster, have 1 person do 5 rides on 1 coaster, have 5 people do 1 ride on 1 coaster, etc.
Must admit I was dubious about it at first, but they seem to have got the numbers right. And if it works like many other European parks who offer similar Fastpass style packages, where they've taken inspiration from, that's only going to be a good thing.