I understand that red is the most popular season for resorts, but what is meant by 52-16?
52 weeks per year. #1 is the first full week in January, generally beginning on either the first Friday, the first Saturday or the first Sunday of the year. #47 is usually Thanksgiving week, #51 is usually Christmas week and #52 is usually New Year's week (the week including the holiday). There are exceptions, depending on the calendar each year. 52-16 means the time spanning from New Year's week through the end of traditional spring break weeks, including Easter week.
The exchange companies (like II) or Member Services can tell you the week number of the specific dates that interest you, if you don't know it.
And how do you know what color season a particular resort will be for the time you want to vacation there?
Again, Member Services can tell you, from their charts, depending upon this new arrangement they've made with II. Orlando is considered red year round. But it's not really all high season, some will trade as mid-season. Vero has mostly red, some yellow/mid-season. HHI has mostly red, some green/low-season. II normally denies upgrades of trades from green to red but DVC has arranged for it in the past (January HHI for a red week elsewhere).
Perhaps this has something to do with why DVC and II made a change. Or perhaps there were too many DVC members who felt that the real/varying number of points given up was unfair when two members could make the same exchange and have to pay different amounts of points, just because availability of deposit week reservations was different due to the time of year when they placed their requests.
Anyway, just as DVC has varying value to their red weeks, so do other regions. Everyone would agree that a July 4th beach week would have more value than a late September beach week, though both may be red. DVC will still want to deposit the lower season red weeks to obtain higher value red weeks for DVC members. But how they have determined this by the charts has still to be seen.
I would guess that the midseason DVC points figures will be used most often, other than for the highest of prime holiday week requests. Since DVC members probably tend to request prime weeks the most (like everyone), this would be fair, IMHO, allowing for a slight upgrade in the exchange due to the quality of DVC resorts. JMHO.