Exoterically, one God can take many identities.
Esoterically, one God's being can have many aspects.
This is why this question is particularly hard to clarify.
"Are Satan and Baalzebul one and the same?"
Yes, they are the same being and "person". Zeus is Baalzebul, Zeus is Satan, Baalzebul is Satan.
"Should we instead use Zeus to communicate?"
Either are fine. Satan, Satanas, Satya, Zeus, Zeus Lucifer, and also names like Odin/Wotan or other identities depending on what you feel closest to.
I've personally found Zeus Lucifer to be the best to call Him, and I am neutral to most mythologies and cultures because of how I was raised, so I'd say this is a good "neutral opinion".
If you are Greek, you might find it very close to home to use Zeus. If you found the Gods by looking into the Enemy's works and reverse engineering, Satan might be close to you. Similarly to if you are an older member.
The same being will pick up the phone.
"Is either Ritual obsolete?"
No. The Rituals serve many roles, including complex Theurgy, because the Gods are not just beings, but also aspects of the Universe, pillars of the Soul, and so much more. Satanas and Baalzebul represent two different pillars of the Soul, and two different aspects of existence, two different "powers of God", etc., but are ultimately the same being. In the Temple, it was told that Satan's Absolution Ritual deals with the parasivanic (before existence) side of things in a much more direct way than Baalzebul's Power Ritual. Note also that one is an Absolution Ritual and one is a Power Ritual.
While I can't explain exactly everything a Ritual does (this is beyond my level by a lot), they do in fact do different things.
"Are Odin and Thor the same person?"
Yes. Zeus, Poseidon and Hades are all the same person. Vishnu, Brahma and Shiva, too. This, while "new information" to some, is not that hard to believe.
It's fine to be confused, these changes will be more clarified with announcements, and more importantly, with time.
In the meantime, do feel free to experiment. Use different names (Satan and Zeus, for example), and see who picks up the phone, etc.
Depending on your level, you might not feel that they are the same being responding, because I also felt different energies at first, but there is a common essence between the two names. Advancement will make this clearer, as there are gaps for me as well.