Unfortunately, many users have reported difficulty going back and forth between different wifi networks using iFly devices, and that behavior has been reported on all of the 7xx models (well, not the 700, because it didn't have a wifi interface). There are numerous threads on this forum about people having trouble maintaining stable network connections due to this issue. The simplest workaround I'm aware of is to forego using a 7xx device on multiple networks, and instead keep only one network's credentials saved on the device so it will only ever try to connect to that network.
I hope that your test is successful, but if you run into issues, remember this information and try deleting all "(Pre)" networks except for the one associated with your ADSB receiver to get back to a stable configuration.