In triple periodization plans the difference is usually the dates of the biggest meet. If it’s late as in late Aug, there is often a down period as far as comps go to get ready for the final series into the Champs. That’s the third cycle, even though it can be very short indeed.
The other two are pretty clear. In an unusual set-up- like the LA 84 Olympics being earlier, it’s most likely to see a double periodized plan.