You can place an ongoing search request up to two years advance.
Your request will be placed in a queue. So the earlier you make your request, the higher you'll be in the queue. High demand resorts and high demand locations especially during peak travel season are going to have long queues.
Here's some additional information about exchanging.
For RCI Weeks inventory
o Weeks can be booked as early as two years in advance and as late as two (2) days prior to check-in (however actual week availability varies by resort).
o It's best to place an ongoing search request as early as possible to get in the queue. What’s normally seen online are the leftovers after all ongoing requests have been satisfied.
For RCI Points inventory
o Weeks and/or nights can be available as early as 10 months in advance and as late as the day of check-in (however actual availability varies by resort).
o RCI Points does not support ongoing search requests. It requires a manual search. Based on the resort, availability can change constantly.
o To increase your odds of getting your desired travel dates it is best to start searching online as soon as the 10 month window begins to increase your odds of getting your desired travel dates (especially for peak travel dates)
HOW IT WORKS:
In order to get a great trade with any timeshare exchange company you need to understand how it works. Some folks start their request too late and/or have unrealistic expectations that anytime they want to travel a week will be available. Once you understand how exchanging works, you'll be better prepared.
It is important to understand that exchangers only have access to what is deposited and not all weeks are deposited. The number of deposits by each resort varies. You will have no idea how many weeks are actually deposited in RCI (for example it could be 1, 10, 30, 60 or 100s), what time of year they make deposits, which weeks do they deposit (Winter, Spring, Fall or Summer week) and where are you in the exchange queue (there could be several folks already ahead of you requesting the same location with equal trading power).
Some destinations will be harder to exchange into than others. It depends on supply and demand. There will be lots of competition for high demand resorts/location during the peak travel seasons. There will be lots of exchange competition at destinations were most folks want to visit (beach areas in the summer, major city, ski resorts during ski season, national park areas, etc). One should expect high owner occupancy during this time which generally means less exchange deposits (NOTE: Some timeshares owners would rather rent their high demand week than deposit it with an exchange company).
With exchange requests, it's best to be as flexible as possible on your requested unit size (there is more competition for larger unit sizes) and travel dates (like any time in 2015/2016) and even then you may not snag a week at your requested resort.
With RCI, it's wise to always research the properties that are listed in the RCI Directory to make sure it meets your vacation needs in terms of location, quality, amenities, etc. Depending on the RCI choices, you may decide to visit this location via some other means (hotel/resort stay, etc).
You can sometimes find reviews on RCI, Tripadvisor, Yelp, various travel related sites and from other fellow TUG members by searching the forums or by accessing the TUG Resort Database.
Keep in mind that RCI trading is not cheap. In addition to your annual maintenance fee, you'll have to pay an RCI exchange fee (currently $209 for a one week stay) and sometimes a resort/housekeeping fee. These fees will continue to rise.
For example, currently a Disney World trade it's an additional $304 dollars ($209 RCI fee + $95 Disney Resort Fee).