Here are MS's recommendations on use of e-mail or on line booking from the MS FAQ's:
1. The Member Services phones can be quite busy, are there other ways for me to make my vacation reservations?
You can submit your Disney Vacation Club Resort vacation request right here on the Members Only web site by clicking on "Plan Your Getaway" and submitting an online reservation request form. Or, you can submit requests by fax. Just be sure to include your name, Member Number, the name of the resort where you'd like to stay, preferred dates and accommodations (include alternates), and the number of Vacation Points you're using. You will receive a response to your request within two business days.
2. Can I make requests via fax and email?
Yes, you can. You can use the Member Services fax and email to:
Bank Vacation Points
Change the number of guests in your party
Request a grocery order form for Disney Vacation Club Resorts or, click on "Plan Your Getaway" on the left navigation bar and print out a faxable form
Change your address or phone number
3. Are there some requests that should not be sent by fax or email?
Yes, there are. Fax and email transactions are not suited for:
Member Getaways options, such as exchanges, cruises, safaris, etc., which require you to have more of a dialogue with Member Services
Priority seating requests for Walt Disney World® Resort dinner shows, which may necessitate several alternative choices
Airline and car rental reservations
Credit card transactions
