I am not sure, do you have any drafts saved ?
I noticed, for example on this it did not show any option to "load draft, however I also did not have any drafts saved. I started
a reply, then saved it as a draft. Then when I came back to this thread, and replied, it does show the option to load the draft I saved.
If there are no drafts saved , it does not show the option, to load a draft, because there
are none. The option does not show until you start a reply, or start a topic.
You can use the "user control" panel to manage your drafts.