Might just be easier to actualy bid a specific placement then. As there are no unclear things no misunderstandings. 1 sub from UK on ZS 110 ( for example ) cannot be misunderstood in anyway.
Also allows for more creative and flexible bids you could bid units in spots you dont have them yet or get multiple units in an area as long as your opponent doesnt mind.
As bidding is a house rule and some have different rules then others.