I have found the box the iPad Mini 2 came in. Put the package together, SIM tool, charger & Lightning cable packed away. Updated to iOS 10.3.1, disconnected it from iCloud/iTunes, waiting on unit to recharge.
Tried to find a frying pan I'd seen advertised in an ALDI catalogue. Not in the three stores I visited. Then I found the notification email. The thing isn't on sale until Wednesday.
#Numpty
Very mysteriously, a few months ago the main user account on this MBA developed a glitch in Safari: the app's icon would bounce up to 31 times in the dock before it opened. A partial fix was to use MainMenu app to clean the Safari cache, this would knock it back to a more acceptable 6 dock bounces, the cache-cleaning operation usually taking three seconds. It was only affected in the one user account, when switched to the troubleshooting account, Safari would behave normally.
Well, I can now report that it has unglitched itself.
Safari now bounces 1 to 1½ times before launching.