Yest the roof of BMW Z4 can be opened by holding the unlock key.
You can click on the following link to see the details of the nearest dealership and selecting your city accordingly - Car Showrooms.
As of now, there is no official update from the brand's side so we would suggest you to wait for the official announcement.
Yes, BMW Z4 is a soft top convertible.
Guaranteed response within 48 hours
On Road Price