After passing level 12,000, I discovered that all levels in each episode I play are rearranged in a different order. I almost always receive a board that is different from those shown in the videos, and it turns out to be a substitute from another level from the same episode. The worst part is that the labeling of levels is left unchanged, so it no longer corresponds to their actual difficulty.
Two examples:
I had a suspicion that something was amiss when two levels marked as 'Normal' needed a strategy similar to one required for Nightmarishly Hard/Legendary levels to pass. Of course, the intentional mislabeling of levels makes it difficult to choose an appropriate strategy to pass them.
Although the two levels above were just swapped, it's not always the case, and the pattern appears to be more complex.
This is the second time I have been subjected to such a test. For the first time, this happened when I was in the early 6,000s, and the test continued until I passed level 7,000. So unfortunately, this can possibly continue for a long time. Given that I have almost no ads and few events to earn boosters, wasting boosters due to level mislabeling will leave me without them really quickly. Unless I can figure out the exact pattern of how levels are rearranged to accurately determine their difficulty, I will likely have to put this account on hold for a while.