Posting time
It can be a Catch-22 when trying to rent out a floating week. By one stretch, it looks attractive to a renter when he sees the available times. There's a range of times available. We see this a lot in RedWeek ads. For example, an ad for a floating week for rent might read under the "Dates" column "February 10-December 31, 2015". A potential renter might like that idea because it looks flexible and can suit his vacation schedule.
But on the other hand, in order to get a high-demand week, the owner usually has to book a specific week at the very moment a floating week becomes available to rent. So in your example, a 2016 week might be available for grabs in July of this year. That would mean that this July, you would have to book a specific week in 2016 before other owners at the resort book it. That now takes away the attractiveness of posting a floating week for rent. So your ad can no longer say available February 10-December 31.
So I guess the best time to post your ad for a floating week depends on which route you choose: book a high-demand but specific week or wait until you get a response to your ad and try to book a week but be left with the leftovers (read: "Dog Weeks").
Most would recommend booking a high-demand, but specific week as soon as it's available to book because there will be a better chance to find a renter than waiting for a "dog" week. As for the best time to post it, I would post it as soon as you have confirmed that you have that high-demand week. Many high-demand weeks get inquiries as soon as they are posted.
Lance C.