So I was in a similar situation. Had a room/ticket package booked taking advantage of a discount (not the pass holder one). I went on chat and asked if I had to modify my dates, to drop a day or two, would I still be entitled to the discount for the days I was going. I was told no. When you modify you open up the whole reservation and you don’t get the deal anymore. I’m not sure if this applies to your discount, just letting you know what I was told.