from singapore to johor bahru airport? - 馬來西亞

could anyone give me some advice?
I'm really afraid about the criminal news recently..
but already planed to visit malysia on July..

We will take subway from Singapore to Johor Bahru airport..
our flight depart on 9:25, Thursday morning..
I guess we should arrive airport on 8:00(asia air)

do you think can we make it to arrive on time if we
take subway from singapore to Johor Bahru ?
(we will try to catch up the first subway)

by the way..we need to pass both custom..

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