I recently asked this question to an agency that works for Logitech Switzerland. Their answer:
At the moment, we expect the keyboard to be released around October, but I can't tell you anything more precise than that, and the information is of course without guarantee.
Dear Digitec team, unfortunately Logitech doesn't provide any information, I've been asking again and again since spring. As a major distributor, you certainly have more influence, so please stand by Logitech. Wouldn't it be strange that a Swiss company is not able to print a keyboard with a Swiss layout?