My parents are getting divorced and I am taking over the home ownership, because my mother is ineligible to do so. How to pay down the loan quickly, and how many years I should pay it within?

I don't think there is fixed rate 1.6% for 3 years anymore. It's more like 1.9% now.

Sorry to hear about your situation. Hope somehow things can be resolved peacefully at home. Hdb loan or bank loan. The former will be a wiser choice, even with the higher rate currently. True that bank loans may have lower rates for now but with the Fed in the US raising interest rates recently, with one more hike this year and a few more next year, it's gonna be very likely sibor will rise also. And bank loan rates in tandem. Calculate the likely repayment rate for CPF based on the maximum loan period you can take, then see if you can contribute a higher amount than the suggested monthly repayment. This will help to bring the loan quantum down quicker and reduce the repayment period as well. I just did the same for my hdb loan recently as well. Hope this helps