Its still all completely unclear and spokepersons are all talking different things on different days. IF interested, follow a normal mainstream news site or thai forum.
But the main guy from the TAT=tourist office told that it now means 1 day of quarantaine in a prebooked place-so that the big govmt. can contact you and apparently do their thing.
Even if for myself would have booked in normal times I simply wait and see what the final word will be.
Interestingly tourist-packages are still big on the market here again-the tipical flight+14 days HTL for 999 eur (PHuket or HuaHin) and other reports tell that airlines will not give away free frequent flyer bonus seats to BKK as they want to sell as much/as expensive/ as can do asap.