When does the Pokemon Tretta trading time show up?

I have been playing Pokemon Tretta for years now. For those of you who do not know it, Pokemon Tretta is an arcade game with physical chips. You scan them and battle 3 vs 3.

I already know that there are 16 Pokemon Tretta chips revolving in the machine aside from the other chips in the stack. The ones revolving are the chips that will be in the preview (we have 3 pokemon per preview) and 6 out of the 16 with be at the "select your destination"

After the game you will be given a chance to throw pokeballs and if you're lucky there will be a trade chance for the one you caught.

I want to know if there are certain conditions that increase the chance for trading time. Or how will they appear.