Couple issues. Yes the railing needs to come off to chnge the roof. The railing reinstallation needs to be done with as few attachment points thru the roof as possible.

Thanks. I keep thinking there has to be an easier way but haven’t discovered it yet!

" I keep thinking there has to be an easier way but haven’t discovered it yet! "

Unfortunately there is not. How was the whole magilla constructed? What do the posts actually attach to?

The key to this is in the details.

If you were to build something like this, you can either:

• Fasten the posts through the roof proper, where each post will have it's own post boot (google image for prefab examples), and 30 years later when the roof needs replaced the railing can remain and the membrane is cut around it with new boots installed. Most likely a wood railing will need be replaced first and new boots can be installed anytime over existing membrane.
• Fasten the posts into a parapet, which is separate from the roof membrane. The parapet would have it's own cap and boot flashing and the roof membrane can be replaced independently.

As mentioned by others detailing is the key to the choices, especially for roof drainage and whether this is just a decorative or usable space, and the look may change aesthetically for each choice.

I don't imagine you can expect any type of warranty on the installation of a membrane roof unless it's done by a contractor who has obtained some type of training by the company that sells the membrane.

The posts will come through the roof and be flashed but my understanding is when the roof has to be replaced the posts need to be flashed again and the only way to do that is to remove the whole rail. I personally can’t believe there is not a better way.