I do not work for Jetstar. I am a Singaporean who has previously worked for CAAS and Changi Airport.
If anyone should be pissed, it should be SQ. CAAS has basically allowed an Australian Airline to get a SIngapore AOC and compete with SQ in its own home terminal. SQ now has to share its air traffic rights with Jetstar and the QF Group. Through SIN's very liberal air traffic rights, QF through 3K's AOC can get neary complete 3rd and 4th freedom open skies to most of Asia, the Mid East and Europe.
These are rights SQ fought for decades, and QF now has them handed to them on a platter. When 3K starts ATH and FCO, they'll probably crush SQ's thrice weekly services to those cities.
So it's not like SQ's parent, the govt, has done them any favours. In fact, SQ's marketshare in SIN has fallen from 50% 10 years ago to 37% today, and the SIN govt has done them few favours.
However on balance the QF Jetstar SIN base is probably of net positive benefit to Singapore as a whole, while it is net negative for SQ. So thats why CAAS and Changi are quite happy with the arrangement.
Out of curiosity, are any of the Jetstar A330 Captains flying SIN-MEL and SIN-AKL Singaporeans? I think most of them are Australians posted to Singapore.