Possibly, if you get back and into NS before reaching the age of majority although this would probably be a first or very rare. Let me relate something as see how it sits.
My boss, a Singaporean business owner and card carrying PAP member is married to a European and they have two children who were born overseas and hold foreign citizenship and were born overseas. Both went to school here (at
International Schools). Neither have taken up Citizenship but the eldest one (the girl) was and still is a PR as she is still single and living at home. Both of them went overseas for their University Educations but did all their basic schooling in Singapore up through O levels, her as a PR and him on a Student Visa. When he wanted to return to Singapore we tried to get him a position in the Father's company so applied for the relevant EP and was rejected. (On two separate occasions) Both times with a paragraph that read basically like "you have unresolved issues with the CMPB which must be addressed before you can be considered for an EP. (He holds a MS in a hard engineering discipline from a UK university. He's about 25 now and still unable to obtain anything more than a standard SVP here. Why? Because they know what his Singaporean father did to avoid NS for the son and they have a long, long, unforgiving memory, looking for ways to prove a point. I told the father what was going to happen 8 years ago (I've been with the company for 11+ years, but he's like a lot of local businessmen who think they know everything. I can only say today "I told you so". What to do?
So, all I can say is Good Luck, as I feel you are going to need a healthy dose of it before this is over.