Would it not make more sense to just sell the Xperia 1 and buy a 10 III (once SFOS for the Mk.III comes out) should you already own it?
It is very, very unlikely they will support the Xperia 1 III ever (they only focused on the 10, 10 II, 10 III so far) as they don’t have unlimited resources and you would probably be the single person using it anyway 
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