They were very clear, they said based on they sources that new Switch version is coming next year, they dont know if this will be Pro or Mini/Pocket/Lite version, they even said that specs are still not finalized, only detail that they did mentioned is that Nintendo is looking at better less power screen thats not OLED.
Also WSJ before reported that Nintendo is planing/working on revision, but this is first time we have info when that revision could come.
Nintendo sources different screens for 3DS but adopts them “silently” without anyone being able to tell from the box. They could introduce new screens for the Switch without changing the consumer-facing product at all. I can't see how there can be a release date for 2019 when Nintendo hasn't even finalised specs, let alone created a working prototype. At best it's an “aspiration” to release in 2019.