Advice- need a response ASAP

Question, so the hospital called me saying to be there by 8:30 for surgery, BUT on the directions and paperwork that were sent to me it says to be by the hospital at 8AM and surgery is at 10am.. does this mean the surgery will be at 8:30? Or the surgery will still be the same time at 10am, but I just be at the hospital a little later? Dumb me didn’t ask them on the phone because they were speaking a mile a minute and surgery is tomorrow