When can the new iPads and Apple TV be ordered?

I can see that they will be available to order on 4-30, but recently they had a standard time that ordering would be able to start. Is that the same and where can I find this out? I can see nothing on the Apple site that is obvious.

For the AirTags last week, it was 8am EDT (5am PDT).

The new Apple TV Siri Remote is “not currently available” in Australia (it is 30th April here)!