Chris, thanks for using our plans. Because recovery from swimming is so quick, you have significant flexibility in moving swim workouts. In general, you can move swim workouts to any other day of the week with little consequence.
The “perfect” adjustment would be to align the swim workout intensity to the opposite of your bike or run workout intensity that day. For example, if your swim workout is high intensity, move it to a day where the bike or run are low intensity. If your swim is low intensity, move it to a day where the bike or run are high intensity. But again, moving swims to any day is just fine.
David