I realise 5S supply would be very, very constrained initially... so how well did introducing the 5C unconstrained at launch work?

I think the 'champagne' phone would have sold out in the launch weekend, regardless of supply. Is Apple playing this out? (yes).

Every customer lining up, or entering stores are dropping almost a grand. You want to keep some top tier 64gb 'space grey' in stock, to sop up those who missed out on a different alloy.

And everyone who isn't eligible to upgrade? Well you get a fantastic OS, and you can buy a nice case! Well played Apple. And I mean that without bitterness. Great product launch.