Could I create an iNPC and add their whole backstory and everything to my encyclopedia, but add a note that says it isn't approved yet and no roleplay opportunities are available with the character yet? Just to map out their whole personality and whatnot until an opportunity becomes available to register an iNPC?

I think someone even did it before, so it should be ok. Maybe if you title the post "iNPC in Creation" or so and, as you said, you can't rp with them.
@Lizzy Solace

Sorry for false info!

Hello, please do not create the inpc anywhere in the encyclopedia section. You can draft it in Google docs or notepad or any off site source that you wish to, or even on the site drafts. However, HOH will make your inpc thread ourselves IF and when the inpc is approved. When it reopens (likely around Spring next year), you will be able to post it then for approval. Thank you.

Okay, thanks very much!

@Opeila Winters, someone else did do that, I just wanted to check to be sure it was okay first, but thank you all the same!