I can’t remember the cost, but we bought a Skyline passport on a 7-night cruise in September. We tried to purchase one on a 3-night cruise in April, but were told that you can’t buy passports on the short(er?) cruises.
No Sorry. They didn't push it and I only heard it mentioned one night by the entertainment close to the end of our cruise. It is a map and you visit the different bars around LaPiazza I think to complete the journey. (Irish Pub, French champagne.....)