The ACT reuses tests?

I noticed that some lists listing released tests skip periods because they claim the ACT re-used the last test for that test date. Is this really true? How long do they wait usually before reusing the same test?

It is 100% true, you should memorize all the past tests, then take the act exactly 7 years after one of your memorized tests, you will for sure get 36

Lest anyone take that reply seriously, let me note that it is sarcasm.