Facebook has a great Facebook Live Producer interface, which includes additional broadcast settings, the ability to edit your details, plus features such as polls.
To access Facebook Live Producer, once you have scheduled a broadcast or started a live stream, view the announcement post or live stream in your browser by pressing command - F in Ecamm Live.
On the Facebook post, click the the Edit Your Details button in the bottom corner of the post image:
The Live Producer window will show up. Note that you may need to pick Schedule a Live Video in the Producer left-hand sidebar.
You can now use Facebook Live Producer to edit then broadcast as needed, including rescheduling, changing the description, or adding an announcement image.
When finished, click Update Post in the bottom left corner.