We didn't take the Olife excursion option. We did the drink package instead.
We got the discount by booking 4 excursions. We actually ended up booking 5, but the discount was there once we booked 4.
Our September 10th cruise on Insignia is 11 days.
We have 8 port days at 6 ports.
For us the minimum is 4 excursions purchased to get the 25% discount.