www.onemotoring.com.sg
you may wanna try this website.
anyway im a new car owner, and my current road tax is to expire in
may. recently i received the new unvalidated road tax disc from
them, asking me to pay the road tax to get it validated. i
eventually did it online, thus removing the hassle of doing it
personally. so i guess yah, they do "remind" you to renew the road
tax.