In 2015 the syrup grading system was changed to better describe the differences between the grades. Instead of the A,B,C system of old, that implied different degrees of quality, all grades are grade A, some lighter and more delicately flavored and others darker and more robust. Syrup tends to be lightest when it's really running hard in the earlier part of the season. As temperatures warm up more complex sugars form and the syrup gets darker and richer tasting.
The new grades are: Golden - delicate taste, Amber - Rich taste, Dark - robust taste and Very Dark - strong taste. Taste them all and decide which one is your favorite!