yup, remember that even you are in ITE, you can go to Poly also.
(MUST ask the people there before you register for ITE).
Or you can try to adapt to the new class, goto Sec 5N, which is
good, why? cuz, anyway, its less than a year in Sec.5, as from Jan
to Sept at most, then its prelims and N levels already, so dun have
to adapt to new class much also.
Ofcuz try to mix around with new class but remember you task is to
study not play a fool and waste your 1 year then fail N levels!
then off you go to POLY! 
and a bright future awaits you.
