We use the Dependent Care FSA for my daughter's (3 yrs old) preschool, she goes 3x times a week. The place has differing hours, she could go in just the morning, all day, just the afternoon,et c. As far as I can tell, as long as it's a preschool or something similar with an address and Tax ID, it's fine. I fax the receipt in one a month and get the money in about a week.

I'm not exactly sure what a "mother's day out type program is" - is it more of a drop-in place? As long as it's a business with a tax ID, I can't see why UHC wouldn't allow the reimbursement. Of course, UHC just follows the IRS, so they're the ones to look for the final word.