The E2 levels can surprise and pop up. E2 has doubled since last scan two days ago - or not? Can't remember now? Hmmm, think you are growing the lead by 1mm per day but they can grow faster toward the end. Holding on to follicles with ganerilix is not a great idea, like the pp said.
Friday you head in for another u/s and bw? If so, I'd decide then or even wait to Saturday to see as sure you'd go in Sat again for a scan? You may want to keep taking the meds for the next few days to make sure you get those two - possibly three if the 8 catches up. If it looks like you will go to retrieval around your time out of town just cancel in the end. You have plenty of time to decide on whether to cancel in my opinion.