Best bet is to wait for the government to announce the opening of the "sandbox" and the conditions associated with it. Anything else is proposals and speculation. I certainly wouldn't be booking any flights, unless you're prepared to wait months for a refund.
Derek Silva. I find it convenient to take a photo of the card, as it's so easily lost, and at least then you have the number. I got severely told off once at CW immigration because it wasn't stapled in my passport!
The important thing about the "departure card" is actually the serial number as this is the same as the "arrival card" and ties in with that. When you do 90-day online reporting it asks for the TM6 number but not any departure date or flight.
Curtis N Christine Quinn. Hopping around SE Asia is likely to be a year or longer away. At your age you could get a student visa or a non-B, which is a work visa. If you've got money to burn, you can get Elite Visa