Orbi Connecting

I had a HORRIBLE time connecting my recently purchased ORBI. QC codes did not work in the app and manual pairing attempts failed (can not detect) multiple times. After multiple attempts, the RBS50v2 finally connected with the RBR50 as the router, the RBS50 as a satellite, and my new RBS50v2 as the other satellite (basically forming an upside down "Y" in the ORBI app. Last night when I went to bed, I checked on the ORBI and it now shows the satellites connected in parallel with one another?!?!? In other words, the Router is connected to a satellite and that satellite is connected to the new RBS50v2 Orbi. Few questions:

Why did that happen- "Y" configuration changing to parallel?
Is there any advantage to having them in parallel?
Is it better to have them connected in the upside down "Y" as it was initially (I'm guessing there is an advantage to having it this way)
What is the speed difference between the 2 configurations
What would you recommend?

Thank you :)