iOS6

With the new iOS (and the development tools that come with it), the original iPhone and iPhone 3G will no longer be supported. It'll no be possible to submit updates that support these devices.
iPhone 3GS, 4, 4S and 5 will still be supported.

All 3 iPad generations should still be supported, even though iPad1 won't be able to upgrade to iOS6, but that doesn't effect iRegatta.