Try swapping other berries for the blackberries. Strawberries, blueberries and raspberries would all work and would be equally delicious!
The syrup can be made ahead of time and stored in the fridge until ready to use. Before serving, allow syrup to come to room temperature or reheat on the stove or in the microwave.
To freeze pancakes, place on waxed or parchment paper-lined cookie sheet. Cover, and place in freezer 30 minutes. After 30 minutes, transfer to plastic freezer bag, and freeze. When ready to eat, thaw in microwave 2 to 3 minutes.