Lets do some math:
140k iPhone 6+ per day
400k iPhone 6 per day.
Reports of July ramp up, lets put 6 working days in there:
140*26 = 3.64M units before launch
400*26 = 10.4M units before launch
And its still NOT ENOUGH?! Dang it Apple, get your act together!
I don't believe those "ramping up" reports to be what the production lines are now. Ramping up consists of hiring a lot of workers, training them and setting up the assembly lines. Then they do small runs. Those units are for the elite (many leaks from all over the world show people with finished units already) and reviewers which have just been delivered. Then the production lines slowly ramp up to finally output 100,000 phones a day but this probably takes a while to get unto speed. Also consider that these are not finished, packaged products ready to ship the the U.S. They need to go through a few more stages (polishing, QA, software loads) after the main assembly.
My point is that by now Apple has built and begun shipping millions but they can only get so far ahead when secrecy is so important to them. If they truly wanted to build up 20 million in advance they could but then the leaks would occur weeks in advance of the announcements with finished iPhones. And what low wage worker would say no to a pile of cash for sneaking out a new iPhone. Their run at that factory is probably done (since Apple has all those finished phones) so many would risk getting caught.
This scarcity of supply is not false but Apple has created their own problems by being so secretive and also trying to deliver 50 million devices in a few months time.
The only possible remedy is to move certain production lines to the U.S. but then you also raise the stakes and money for a leaked device so it might be an impossible solution.
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Pray tell how the apps will look like a blown up mess, when Apple has already stated that they have implemented desktop class screen scaling?
Have you read the reviews? Twitter looks good. Gmail looks bad. Apple can implement hardware/software scaling on their end but until developers address their apps specifically, the quality will vary from app to app.
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I think Apple vastly underestimated the demand for the Plus. According to many polls I've seen it's almost 50/50 but they are producing A LOT less. Screen yields aside, it seems they simply underestimated demand.
If these reports are true, the 6+ screen yield rates are about 50%. Assuming over 90% yields on the 6 screens leaves us with about half as many 6+ phones as 6 phones. That sounds like they estimated the demand right but didn't anticipate the yield rates correctly.