I took practice tests 79 and 80 early on into my studying so as to avoid burning through the more recent tests before I felt ready. I'm now starting to work my way through the more recent tests in preparation for my sitting in June. I was pretty disappointed to find out that Test 79 was identical to Test 148 (at least as far as I got into it), and then the same thing happened between Test 80 and Test 149 (admittedly, I didn't make it as far into this test). And then earlier today, I randomly took Test 26 because I wanted more practice, only to find that one of the RC passages was identical to one that I had just taken from Test 103.

I'm not exactly sure how this whole thing works, but it's inconvenient to keep running into repeats when I'm trying to simulate test conditions. Can someone explain whether there's any method to this madness and whether there's anything I can do to avoid double-dipping?