What titles are unable to be created once another forms?

[0rth0d0xypr0xy]

In my particular circumstance, I'm playing as the Etichonids and have just formed Habsburg Castle through the special event. What I want to know is if I create the Kingdom of Bavaria, will the option to create the Archduchy of Austria necessarily become unavailable?

I thought I'd make this a more general post: for instance, once those Venetians sabotage a crusade and capture Constantinople to form the Latin Empire, does the Byzantine Empire cease to exist? I'm told a similar situation exists in the Iron Century start if players want to realise Thankmar's ambitions & dispense with the HRE.

Thanks for your comments in advance. Got an AAR to complete tomorrow, but have been very busy as of late!

 

[Andrew0Red]

Pointers for starting out:

https://ck2.paradoxwikis.com/Kingdoms#See_also
Well, the last lines of the previous paragraph.

https://ck2.paradoxwikis.com/Decisions#Form_HRE_early
That and the next few decisions.

But I'm pretty sure there are others as well.

 

[0rth0d0xypr0xy]

Thanks Andrew0Red, just for clarification - if I pursue the "Gather the Eastern Marches" by making Kingdom of Bavaria does that mean Austria becomes dejure as opposed to merely titular with the Archduchy decision?