Send another email with the same thread-id with the updated info and when you navigate in Gmail’s UI to the thread the most recent message is shown and the rest is collapsed. This is already possible. You could add some metadata to make this intentional, e.g. message-type: notification and message-obsoletes-id: <prev msg id>... something like that.

The AMP’s schtick is to make emails into widgets. It’s not so much that it’s bad (potentially evil, though), but it makes email into a completely different thing.

In my mind first it’s AMP, then Android Instant Apps or something, and before you know it you have DRM in your emails.

I personally would prefer the current system. Initial email or no email changes ever. Initial email lists the original times. If changes, airline sends another new email.

I feel the fact that the flight changed time on you is also useful information. Say if they feel that because they can dynamically update the original email it absolves them of the need to specifically make you aware of this change. Then you miss a plane, with no proof they have even pulled the rug on you.

You receive an email for your flight: tomorrow at 10am. When you arrive at the airport, you are told the flight has already departed.

"How is that possible, it is 9am and my flight is at 10am?"

"No sir, your flight was at 8am"

Checking your email, you see 8am and you have questions about your sanity