This is response I got and I notice a few omissions...
Thank you for contacting the Walt Disney World® Resort!
Club Level Concierge accommodations are available at select Disney Resorts. Concierge benefits include personalized front desk and Guest Services, daily turndown service, and exclusive access to the Club Level Concierge Lounge which offers complimentary refreshments throughout the day. The Club Level Lounge is open daily from 7:00 a.m. until 10:00 p.m. Generally speaking, from 7:00 a.m. until 10:30 a.m., you can expect to find pastries, fruit, cereal, and beverages (there is no set limit to the number of beverages allowed per meal period or throughout the day). From 12:00 p.m. until 4:00 p.m., you can expect to find cookies, chips, and assorted snacks. From 5:00 p.m. until 7:00 p.m., you can expect to find hot item samples from the resort restaurants, a cheese tray, wine and beer. From 8:00 p.m. until 10:00 p.m., you can expect to find whole fresh fruit and beverages. Exact hours and items may vary depending on the Club Level lounge.
...They don't specifically mention mimosas though they do mention beer and wine. They also don't mention desserts at 8pm. Just fresh fruit and beverages.