Did you know the F-35 will fly at mach 6 with its current singular engine variant if it uses the hydrogen jet fuel without the fuel cell but the fuel cell will help flight duration with 2 days of flying time?

Did you know the F-35 will fly at mach 6 with its current singular engine variant if it uses the hydrogen jet  fuel without the fuel cell but the fuel cell will help flight duration with 2 days of flying time?