Let's see....new member with asian-ish sounding name making numerous posts about a new iPhone bumper made in Korea. Is anyone else smelling a canned pork product?
And seriously, you can't use 30 pin to lightning adapters with this bumper. Retool the sucker and make the bottom open!
And to respond to the OP, maybe the case manufacturers are waiting to see if Apple's going to keep the design and upgrade the internals before they release new products. If I were a case manufacturer now, I'd hesitate to spend thousands of dollars and months to design and build a product; Apple could be releasing a completely new design in a few months as far as we know.
I've found that the sanest question I can ask myself is 'Am I going crazy?' --Jack Robbins
2012 base 15" rMBP, 2012 base 11" MBA, late 2011 2.4 i7 17" MBP, 16 gb ram, Crucial M4 512gb SSD