We are doing the Med with a bunch of my family this June. Originally we were going to book private excursions, but my mom has since become sick and we've all decided to do Disney excursions instead. I was able to sign me, my husband and our kids up for what we want (we're Silver) but I'm worried that the excursions we're booked on will be sold out before I can sign my other family members up. Are some spots held back for booking onboard? Does anyone know if they hold back spots on each excursion or just some? I'll need to sign my aunt, uncle and father up once their booking window opens. It's likely my mom will stay onboard the whole time. Anyone have any experience with this? Thank you!