Lemon Juice Expiration?
If you've waited that long before needing a cup of lemon tea, I'm sure you can wait until you've had time to go to the shop for a new bottle ;)

Bin it, don't risk it.

The expiry date, btw is only for unopened. Once opened it will have a significantly shorter life - checking one from the fridge here it says "Once opened, keep refrigerated &amp; use within 4 weeks" even though the full unopened expiry date is another year away.