Employment contract / Offer Letter

Hi , I just Want to check if you already sign an employment contract and offer letter with the company
Will the company back out ?
But the employment contract stated its depends on MOM approval of the passes
I'm Malaysian .

Second,
Can I still stay at my current company if the past still not yet cancelled but already submit IR21 ?

First question: answer is yes as employer has the rights to do so if they found a Singaporean for that role or they decided to postpone or redundant the role.

For second question: answer is yes but the existing employer needs to withdraw the submission of your pass cancellation at MoM. Good luck

But if a big company and already signed
Usually will they back out ?

The pass can't be cancel until the last day I'm here
Only the IR21 for Iras
Can withdraw back ?

It does matter whether it's a big or small company but an employer has rights to do so, if it's required. I have given the reasons, which an employer may be opted for. But, normally big firms don't do that.

They had apply the application for me and it's approved in the same day .