You subs are called "Account Upgrades" The account upgrades page will let you purchase a new subscription and it will also show you when existing subscriptions expire.
Click on your name on the top right of the blue menu bar. Then choose Account Upgrades.
Available upgrades are shown, and below those you'll see any existing purchases along with a date they expire.
Click on your name on the top right of the blue menu bar. Then choose Account Upgrades.
Available upgrades are shown, and below those you'll see any existing purchases along with a date they expire.