“The Sapling Roadmap” doesn’t include “Ethereum Support” per se. We’re prioritizing Cross-Chain Atomic Transactions (XCAT) first, instead of other flavors of Ethereum integration, because XCAT can be implemented and deployed sooner (i.e. months instead of years), because it is simpler and easier for us to reason about the security properties, and because it will enable Zcash↔Bitcoin integration as well Zcash↔Ethereum integration.
I’ll try to give a time estimate, but I need you to explain in more detail what kind of functionality you’re asking about, first.