As I said, she did not complete her singapore citizenship application. The process is only completed when she produced the final letter from china to declare that she is no longer china citizen. Prior to this letter, she may get her provisional pink IC if she has made application to renounce with china.
Her case as described on internet is very weird because if she want to revert back to china citizenship, it will take time, and china may not accept. Furthermore any moron in china will happily give up their china citizenship for anything else other than North Korea.
Don't believe me? Go ask any prc with half a brain. Prc will give up their first born for singapore citizenship, and some will use it as springboard to another developed country. No sane prc will jump back to china citizenship.
Just because you read it on Internet doesn't make it true. Have you verified? Don't be naive.