Wine tastings - so many on a 4 day cruise????

[Shiba_Lover]

We have a 4 night cruise in February.  There is one sea day and 2 ports days.  There are 4 wine tastings (along with scotch and other tastings) available to book.  I am assuming they do not actually hold all of these?  I've not done a cruise with only one sea day before.   How does it really work?  Will they see which are most popular and cancel the ones that don't get many people?  Will they then ask us if we want to move to the (one?) they do hold?  If I sign up for 2 (assuming they hold 2 and one is on a port day or at same time or back to back with the other - can we cancel one?  I'm assuming they don't schedule it in the middle of they day on a port day?  Thanks everyone!