From an ATGS thread I forgot about (and I started oddly enough) here's John Sergent...
They played 7-11 and Mystery 7 on Monday, Wednesday, and
Friday. Tuesday and Thursday Mystery 7 got moved to the first half and
Double Trouble (1 and 2) added to the second half. After the second
tournament (so, for the last third of the first season) Gamble for a
Grand replaced 7-11. After the fourth tournament (so, for the last half
of the second season) they used Gamble on Tuesdays and Thursdays too
instead of Mystery 7, played for a prize.
My note: Remember too, that Double Trouble really wasn't "special" - each team was required to pick 1 of the 2 sets during the game. Now, those with episodes can shed light as to when these picks had to be made, and etc.
-Jason