No way to make a meaningful link - other than some notes possibly added to the record that'll never be read.

Best not to worry - do whatever switching you can online a few days before and if still not together, trade on the plane. With that said, in J, there's very few configurations that make traveling together an enjoyable experience. I travel with my wife a lot and we may say less than 10 words to each other in the whole flight due to the privacy screens, noise, etc.