El Tor and Tor are two separate networks (for many technical reasons) but we are architecting the El Tor daemon (eltord) and VPN-like apps (eltor-app) to detect what network you are attempting to route thru.

For instance, if you are trying to access your existing start9 that runs on the existing Tor network it will route thru a free circuit (since the introductory and rendezvous nodes are on the original Tor network).

If you are trying to route to a hidden service on El Tor (or even just a clearnet website) it will detect that you configured a wallet and will look up paid relays and their rates via the El Tor Directory Authorities. Then it will build a paid circuit.

The digram above shows much of this logic occurring in the SOCK5 load balancer/proxy in eltord. The goal is to create a modular daemon that could run in Start9, Umbrel, Mobile Apps, etc... and be a drop in replace for Tor.