The last I checked, The Project is generally 4th in the Sydney ratings at 7pm behind ACA, ABC News and Home & Away. I'm not so sure about the Sydney ratings of The Project's 6.30pm portion, but I suspect that it gets absolutely smashed by the 2nd half of Seven and Nine's news bulletins.
Personally I'd suggest continuing with the odd week or two of shows presented in Sydney throughout 2017. While they're up here, Ten/Roving Productions should probably also consider getting Carrie, Waleed and Pete to do some interviews on local radio and the papers to generate some interest in the program amongst the many Sydneysiders who don't regularly watch the show at the moment.
Personally I'd prefer a Sydney edition of The Project (yes, I'll always fly the flag for quality non-news local TV just for Sydney) but the chances of that happening anytime soon are slim to none of course.