Hi Sharleen,
Thank you so much for visiting the Disney Parks Moms Panel with your question. I am so excited for you that you are staying at
Bay Lake Tower at Disney's Contemporary Resort. I love the sleek and modern feel at Bay Lake Tower, and the ability to walk to Magic Kingdom is wonderful!
Let me share some information with you about Disney's Rapid Fill mug program. You can purchase the Rapid Fill mugs at your resort. These mugs will be refillable at Walt Disney World resorts; however, they are not refillable in the theme parks. You can refill your mug with beverages from the beverage station such as sodas, as well as with hot beverages such as tea, hot cocoa or coffee. The Rapid Fill mugs will be good for the length of your stay.
There is great information about Disney's Rapid Fill mugs on the unofficial site disneyfoodblog.com. Once you visit the site, search for "refillable mugs" to find this information.
I hope that this information is helpful for you, Sharleen. Have a wonderful time planning your Walt Disney World vacation, and please do not hesitate to ask if you have any further questions.