I'm not afraid to tell you that SQ's ideal ages for cadet pilots are: 26 for Singaporeans and around twenties for foreigners.
Unless you are applying as a Direct-intake Captain, then any age or nationality will be welcomed. (Provided they are type-rated in the a/c which SQ uses)
Don't give up your dream of flying just because of your age. There are many older low-time pilots (because they started late in their careers) who are flying freighters. So, maybe this could be one avenue for you to consider.