Here is a premise:
Following establishment of this initial mail classification schedule, a 3623(b) provides that the Postal Service may from time to time request that the Commission submit, or the Commission may submit to the Governors on its own initiative, a recommended decision on changes in the mail classification schedule.

Here is a hypothesis:
The initial mail classification schedule may be changed with a 3623(b).

Is it possible to conclude that if the premise is true, then so is the hypothesis?
yes