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We set MIN_SECOND_GUARD_LIFETIME to 1 day, and MAX_SECOND_GUARD_LIFETIME
to 45 days inclusive, for an average rotation rate of 29.5 days, using
the max(X,X) distribution specified in Section 3.3.
We set MIN_THIRD_GUARD_LIFETIME to 1 hour, and MAX_THIRD_GUARD_LIFETIME
to 48 hours inclusive, for an average rotation rate of 31.5 hours, using
the max(X,X) distribution specified in Section 3.3.