The site says it is to be a mid-week service.
This follows a long-running local campaign (The Area News, Griffith's local paper, reported on this late last year)
https://transportnsw.info/news/2019/new-train-services-for-griffith#regional-carousel
It is interesting that they are planning to do this (obvious state election considerations aside), as there is a well known shortage of rolling stock, and the weekend service is already frequently cancelled for one reason or another. That said, at least a mid-week service would not be so much at the mercy of the dreaded weekend trackwork.
The WIN News Facebook page also has the story, as does the mighty Cootamundra Herald.