On: I’ll never bring my phone on an international flig...

[psynapse]

This is how I would do it.

Take a backup and upload (encrypted) to the cloud. Factory reset in transit. Get where you are going, download and apply.

You might need some of your important numbers written down I suppose.

[koolba → psynapse]

If your tin foil hat is on tight, you wouldn't trust the phone after it's in their possession as they could have placed a rootkit on it.