Q: ipad 4 th gen not updating to 9.3 from 9.2.1 says software is up to date

Apple has temporarily removed the iOS 9.3 update for older devices to deal with some issues it was creating. Best to wait a few days for them to rectify the issues.

The iOS 9.3 update is not available for older devices. It was initially, but then it was pulled due to activation issues. It will be re-released for older devices like the 4th generation iPad in the next few days.

Yes here:

If you can't activate your iPhone, iPad, or iPod touch after installing iOS 9.3 - Apple Support

One more Apple article (that I know of, anyway) = If you can’t activate your iPad 2 (GSM model) after you update to iOS 9.3 - Apple Support

Nice avatar.

Saw it on the news > GoogleImaged it = had to crop it for the avatar