Ann:
The refillable mugs are available with the Deluxe Dining Plan but not the Basic Plan, and it's the Basic Plan that you'll receive if you are coming on Disney's free dining in late summer.
But no worries! If you'd like to get one, you can purchase a refillable mug at your resort for around $12.99 plus tax. It allows you to enjoy all of the sodas, coffee, and in some cases, hot chocolate, that you can
at your resort!
Additionally, I wouldn't worry about getting hungry on the basic dining plan! Our family has been several times and actually doubled up table service credits for a dinner show on our last visit--and didn't miss the meal! I don't know if the plan offers a lot of food or the restaurants! Either way, I offered some advice just recently to a family who had the same question as yours, just click
here to see how easily you can stretch the plan!
Wishing y'all a magical vacation!
Whitney