You don't have to give any notice for Resort Airline Check-In [RAC]. Checking in and printing boarding passes are all taken care of at the desk when you get there. 
It is a separate entity from Magical Express.
If you are switching hotels, you should call DME and ensure they have your departure info, resort reservation, etc...
[FONT=Verdana, Arial, Helvetica, sans-serif]
 *            Resort Airline Check-In Service at your Disney resort is only available            if you are flying domestically (includes Puerto Rico) on the following            airlines: AirTran, Alaska Airlines, American, Continental, Delta, JetBlue,            Southwest, Northwest, United  AND US Airways. It is a complimentary (free) service.[/FONT]
         [FONT=Verdana, Arial, Helvetica, sans-serif][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]
		
		
	
	 As of April 7, 2010, Southwest Airlines is now officially a part of Resort Airline Check-In at  Walt Disney World.  Upon completion of a construction project at Disney's Old Key West    Resort and an assessment at  Caribbean Beach Resort, Resort   Airline  Check-In with Southwest Airlines should be available at every   Walt  Disney World Resort hotel by the end of 2010.[/FONT]
         [FONT=Verdana, Arial, Helvetica, sans-serif]
Participating airlines (domestic flights only):[/FONT]
         [FONT=Verdana, Arial, Helvetica, sans-serif]
-- AirTran Airways
          -- Alaska Airlines
          -- American Airlines
          -- Continental Airlines
        -- Delta Air Lines
        -- JetBlue Airways
        -- Northwest Airlines
        -- Southwest Airlines
        -- United Air Lines
        -- US Airways         [/FONT]
         [FONT=Verdana, Arial, Helvetica, sans-serif]
* This            service allows you to check your luggage and receive your airline boarding            passes right at your resort on the day of your departure.[/FONT]
         
[FONT=Verdana, Arial, Helvetica, sans-serif]-- Guests              who fly AirTran, Continental, Delta, JetBlue, Northwest, and              US Airways may check one bag per passenger using the Resort              Airline Check-in Service. Guests with multiple bags on these airlines              will have the option to check additional pieces through their airlines'              ticket counters at Orlando International Airport or they may call              Baggage Airline Guest Services at 407-284-1231 to pay their              airline's excess luggage fees in advance of checking in at the Resort              Airline Check-In desk. The excess luggage fees vary by airline. [/FONT]
           [FONT=Verdana, Arial, Helvetica, sans-serif]-- Guests              flying on American who wish to check bags must call Baggage              Airline Guest Services at 407-284-1231 to pay their airline bag fees              in advance of checking in at the Resort Airline Check-In desk. Otherwise,              Guests must check-in at the airport.[/FONT]
           [FONT=Verdana, Arial, Helvetica, sans-serif]-- Guests              flying on United Airlines are subject to checked bag fees based              on when they purchased their tickets and when they are flying. Verify              the actual fees with United before traveling.[/FONT]
           [FONT=Verdana, Arial, Helvetica, sans-serif]NOTE:              Each airline has a long list of exceptions to these checked bag              policies. Exceptions may include those who bought before the new rues,              elite frequent fliers (and those traveling with them on the same reservation),              first class passengers, full-fare economy passengers, and government              and military fare passengers. Consult with your airline on its exact              policies before traveling. The Resort Airline Check-in Desk may be              also be able to provide you with airline-specific fee information.[/FONT]
           [FONT=Verdana, Arial, Helvetica, sans-serif]Baggage              Airline Guest Services (the fee collection service, not the Resort              Airline Check-in Desks) operates seven days a week between the hours              of 7 a.m. and 11 p.m. [/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]If              paying for excess luggage fees through Baggage Airline Guest Services              you must pay with a credit card: MasterCard, Visa, and American Express              are accepted. Resort Airline Check-In desks are unable to collect              luggage fees on behalf of the airlines.[/FONT]
           [FONT=Verdana, Arial, Helvetica, sans-serif]For ALL              airlines, luggage must be 50 pounds or less in order to use the service              and it must comply with their airline's size dimension baggage policy.              Overweight and oversized luggage cannot be accepted at the Resort              Airline Check-In desks. [/FONT]
         [FONT=Verdana, Arial, Helvetica, sans-serif]
* This            service is separate from Magical Express. You do not have to            participate in Magical Express to utilize the Resort Airline Check-in            Service.[/FONT]
         [FONT=Verdana, Arial, Helvetica, sans-serif]
* Each            Disney resort has a dedicated Check-In Desk located in or near the Lobby            or near the outside entrance to the resort. If you can't locate the            Resort Airline Check-in Desk, ask at the Front Desk. Some examples:[/FONT]
         
         [FONT=Verdana, Arial, Helvetica, sans-serif]
* The desks            are open every day from 5 a.m. to 1 p.m. You can check in no more than            12 hours and no less than 3 hours prior to your scheduled flight departure            time.[/FONT]
         [FONT=Verdana, Arial, Helvetica, sans-serif]
* To check            in, your entire party must be present with your government issued photo            I.D. (e.g., driver's license, passport, Military ID) and your Key to            the World card to verify that you are a guest of a Disney hotel[/FONT]
         [FONT=Verdana, Arial, Helvetica, sans-serif]
* The Resort            Airline Check-In desks can provide some of the same services and information            as the airline ticket counters at the airport, including checking seat            assignments, and verifying flight information and status. The Resort            Airline Check-In Desks cannot make any changes to flight arrangements            or make new flight reservations.[/FONT]
         [FONT=Verdana, Arial, Helvetica, sans-serif]
* This            service is not provided by Disney. A third-party company approved by            the Transportation Security Administration (TSA) operates the Resort            Airline Check-In on behalf of the participating airlines.[/FONT]
         [FONT=Verdana, Arial, Helvetica, sans-serif]
* Some            persons have reported a wait of over 30 minutes at the Resort Airline            check-in desk during peak times. If you are within 3 hours of your departure            time, you should bypass this service and get your boarding passes at            the airport.[/FONT]