Advice on switching between work passes

[LucyinLondon]

Hello everyone! Hoping you can provide some initial advice on Singapore work passes.

I am an Australian citizen who will be 30 years of age on March 9, 2018. I have a university degree.

I'm currently based in the UK. My employer is sending me to Singapore for four months this year and will be organising an Employment Pass for the duration of that time.

After the four months are up, I would like to apply for the Work and Holiday Visa Programme so I can stay on in Singapore.

My question is - am I allowed to apply for the Work and Holiday program AFTER having held an employment pass? Do I need to leave the country to do so?

Thank you,

Lucy