Yes, by contacting the airline’s office in Israel only. Keep in mind that if you are not planning to return with your group flight you must make your changes before the group return date.
You will be responsible for your own PCR test prior to returning to the US. Note: Participants traveling with other than Israeli passport, wish to travel to other countries at the end of the program, will be required to purchase separate one way ticket back home at your own expense as re-entry in Israel is not permitted this season. BRI tickets have only single entry permit to Israel. Participants with Israeli passport do not need a permit, so they can travel.