A remote seller over the threshold registers with the Louisiana Sales and Use Tax Commission for Remote Sellers, which administers the state and local sales and use tax on remote sales. The official material read does not set a grace period between meeting the threshold and the start of collection, so the prudent reading is that registration and collection are due once the threshold is met; confirm the start date with the state before relying on any delay.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.