The ticket sits in your Android wallet and updates itself if the time or place changes.
Tickets, coupons, loyalty cards, memberships and passes go into Google Wallet with one tap. The card stays live: change the event time and it updates on the guest's phone on its own, with no mailing and no "did you see my email?".
A ticket in email is easy to lose among other messages. A card in the wallet sits where people are used to looking for a boarding pass or loyalty card, and it opens without searching the inbox.
When you reschedule an event, the new time appears right on the card. This guards against the classic "I never saw the email about the change", and with it against empty seats in the room.
Google Wallet works on Android. AOA shows the guest the button for the wallet that works on their device, so they never face an unnecessary choice. The email and Telegram message with the same entry code arrive either way.