You can expect them to cost $1.99 a piece and to come with maple syrup for dipping.
Like the rest of Sonic's breakfast menu, they're available all day.
Update 2/28/17 - Sonic is also offering a few, limited-time breakfast deals: a Lil' Breakfast Griller, with Bacon or Sausage for $1.49 and a Jr. Breakfast Burrito for 99 cents until 10 AM.
Photos via Sonic.
Nutritional Info - Sonic Pancake on a Stick
Calories - 240 (from Fat - 100)
Fat - 11g (Saturated Fat - 3.5g)
Sodium - 370mg
Carbs - 26g (Sugar - 11g)
Protein - 7g