Good news for Z9 owners... According to a marketing sheet for the A1E, the Z9 will definitely be getting DV via an update and it's still the flagship set with the best overall picture.
I'll copy and paste a few FAQ's on the sheet
Is the picture quality of A1 series better than Z9D?
For total balance of picture quality, the flagship Z9D is better than A1E. However, in some aspects--like absolute black level and viewing angle--the A1E has better potential due to the OLED's self-illuminating pixels.
Does the A1E support Dolby Vision?
4K HDR TVs with 4K HDR Processor X1 Extreme supports Dolby Vision, Hybrid Log Gamma, and HDR 10. Other 4K HDR TVs support Hybrid Log Gamma and HDR 10. The newly announced X94E, X93E and A1, as well as our flagship Z9D, will support Dolby Vision via network update.