You must be running CC2015.2 in order to do that. Make sure you’re installed the updates.
Just found the "Update Existing Document" button staring me in the face.
Do those links ever expire?
With digital content, that's always an open question. At some point, a file format will not be used anymore. At some point, a company will go out of business (remember Kodak?) I'm sure it will active as long as the feature exists in InDesign (probably for many years). How long do you want it to be active?
If you want something to last a millennium, print it on acid free paper, and store in carefully controlled conditions.
No quantum physics here...just wanted to be sure the links weren't set to expire at predetermined intervals ... like after a month, etc.