It's still possible at the moment, but nobody knows how long this will last. It's always a short period of time, mostly a few days after a new update is available. It could be over sometime today or tomorrow.
You need a computer with iTunes installed to revert back to iOS 7.1.2, you need to download the specific firmware for your iPad. Apple doesn't support reverting, and it's not covered under warranty, so if you downgrade, it's at your own risk.