I had the following happen when opening 1Password in landscape on an iPhone 6 Plus in landscape (iOS 8.0.2) straight after installing latest beta.
I have a screenshot but see no way to attach it via iOS forums.
Got it to load the screenshot.
Thanks for reporting this! I can reproduce this as well and we'll get that fixed. Stay tuned for more improvements coming for 1Password on iPhone 6 Plus, we're working on optimizing the interface for it.