I was on a 176 FS Cat 5, I tried applying for sponsorship (NSW, QLD, NT) and they all rejected me because the 176 was depreciated and they would only sponsor 190 skillselect applications. Very frustrating as DIAC say you should try to get SS. No way I was cancelling application and paying another $7k for skillselect. Anyway after this I decided to do IELTS for extra points and transfer to 175 independent. I now have a CO 5 years after applying!
If you can change you should.