To nitpick breakfast tea isn't a type of tea. There is English Breakfast Tea which is a specific blend of black tea and spices.
Black tea usually have 50 mg of caffeine per cup, roughly half what coffee has. Oolong, Green, and White tea all have even less. Yerba Mate has more caffeine but that is a different plant than true tea.
None of the English/Irish/Scottish Breakfast Teas are spiced, they're blends but pure tea, and they do tend to feature Assams and other high-caffeine varieties.
