No, that's not right.
Look
For example, a subscription for $3.50 gives you the “standard release,” which is the shortest version.
Let's say an average subscription for $7.50 gives you the “medium/extended” version, which is half of the total running time.
A subscription for $12 gives you the full running time.
And for $15.50, you get the full runtime and the GG ending, as well as an amplified voice in polls and access to all archives.
And no, nothing changes over time. Whatever release was assigned to a particular tier remains the same over time.