Student Pass and S pass Apply Simultaneously

That is an interesting question, which as far as I know was not yet discussed on this forum!

It is definitely not allowed to hold two valid passes at the same time - and the issuing authorities (MoM an ICA) each do also not accept two applications in process at the same time. But whether one at MoM and one at ICA is allowed - I honestly dont know. But this being hyper-effcient Singapore, I expect that there is a rule for this. Ask them! (And, if you get a useful reply, please come back and tell us here, so future readers in the same situation can benefit from it as well!)

As far as I know, you can apply as many passes as you want at the same time, even with same authority (like apply PR and LTVP simultaneously with ICA). I know many people do that and ICA accepted that. Which application gets approval first, accepting that pass has nothing to do with other applications. Only you need to inform other authorities whom your are applying pass to about changes in your pass status if any.