- A frac vote nests a GGovPeriod.vote per re-cast escrow, and that inner vote runs its own checkNeedMBR — which reads `periods` on the gGov registry. Population resolves refs by simulating, so a period that dropped under its minimum balance between simulate and execution failed the whole vote.

- Same fix as the frac registry's `instances` box, one layer down. One slot, not one per escrow: every cast hits the same box. Padding 21 -> 22, fees unchanged.