There is some information about the limits in the vBNT-BNT pool in Bancor Vortex part 2: vBNT Whitelist Proposal which I have shared below. Essentially, my understanding is that we want to start small so that we can observe/test the vortex and what effects it has on the protocol before we update the minting limits.
Progression of the Bancor Vortex and vBNT Pool
The approval of BIP9 by governance is already complete; the approval of this proposal is the final approval step for the envisioned system. The whitelist status of the vBNT pool is ready for deployment already, and will be implemented with a proposed 250,000 BNT minting limit. Thus begins a short period to observe how users interact with the pool, what the leverage appetite is, optimize the front-end and educate the community on responsible use of this novel feature. During this time, the vBNT burning feature will be in its development and auditing process. After the vBNT burn feature begins, the full Bancor Vortex will be in effect. Another short period for testing and observation is then followed by an increase in the minting limit to 1,000,000 BNT. Thereafter, the minting limits are adjustable pending a DAO decision.
