All you have to do is email Mauvette / Andrea at Catcha

stay@catchajamaica.com
or
catchafallingstar2@gmail.com

The cost is for 2, everything included from appetizers, entree, wine/champagne, dessert
How far in advance depends on the time of year I would guess...they only do one seating a night so it would depend on availability and demand
Just email them your date and they will respond with a confirmation, its as easy as that.
Enjoy!