CAAS accepted the Jetstar Asia A320s getting transferred from VH to 9V registration, so there is some predecence?
You're comparing B787s to A320s here Dr. It's not that simple though.
If the A320s that were transferred from VH to 9V registrations were first-of-type on the 9V register, then there would be a 'sort of' precendence transferring B787s onto the 9V register if they were also first-of-type onto that register. Lot's of paperwork involved if that was the case.
But if they weren't first of type onto the register they're being transferred to, then its no big deal transferring a type from one register to another, providing the airworthiness paperwork is acceptable to the State of Registry that you are transferring the aircraft to (more or less, in Golden Book terms!).
But there's absolutely no need to transfer the registrations from VH to 9V registry under an 83
bis arrangement,
providing the CAAS is agreeable to the proposed arrangement.
As I've previously stated, this sort of thing isn't all that straightforward, so others may disagree with my interpretation.