Are you checking on Samsungs own ship site or via a Network or Independent @nkenny ?
On the Samsung UK Online Shop Site that particular model is available > https://www.samsung.com/uk/smartphones/galaxy-z/
Daily Driver > Samsung Galaxy s²² Ultra 256Gb in Phantom Black.
The advice I offer is my own and does not represent Samsung’s position.
I'm here to help. " This is the way. "
I gave up waiting and worse at the time only the 128GB was available in blue, but i have a One Drive Premium account, just need to ensure every few months offload them off the device and just keep the OneDrive versions, as they can be linked via the Samsung gallery.