If there is an upside to being away due to injury.... it has been coming back to see how glorious your garden looks my mate! Definitely have seen discolouration from unexpected frost before so I'd say that's your culprit for sure. Definitely don't see any signs of N excess.
EDIT: I hope I qualify for re-entry into the compound Dug. Just wanted to check with head of security. In all honesty I guess it's too late since I've already gone and wandered on in. If it is of any consolation I'm recovering from a head injury.
Hey GL, it's cool my brotha.....you have already cleared security checks and have full access to Major's garden's. Enjoy your stroll! Cheers...oh, and good morning Major!