What do I do if I need to backboard a person wearing a life vest?

I am a lifeguard at a facility that uses a "blob." For those who don't know, a blob is essentially an air filled matress that guests jump on, one at a time, sending the guest that jumped ahead of them flying into the air into a lake. They are required to wear a life vest, but my training did not cover the eventuality of someone wearing a life vest needing to be backboarded. Are there any instructors that have any tips or perhaps a solution to my conundrum?