Hello,
When we die, we are unable to stay as a vampire lord, even if we have a duplicate bottle of blood from the dragon (to drink it again, if it was on purpose).
We stay into a normal vampire.
I use Minecraft version 1.20.1.
I tested both with a datapack and the mod in version 2.2.0.

Oh, I forgot, I'm using fabric, with fabric Api 0.92.2 for 1.20.1 😅
I'm also using "Aspects", an "Origins Addon"