With bipolar type 1 disorder does hypomania always precede mania?

Bipolar: Not necessarily, but appears more in bipolar type 2 younger females, at least from my experience.

Not always: In type 1 bipolar disorder, the transition from normal (euthymic) mood to mania can be abrupt - without any preceding hypomania.

Not necessarily: Often mood may elevate somewhat slowly so that one is hypomanic on the way to mania. But often, too, the transition to mania is so abrupt that any intermediate state is too short-lived to matter. That said, someone with bipolar I who becomes manic should be concerned that it is an intermediate stage with more severe symptoms to come.