So you are telling people it's ok to die early because you are going to die eventually. Get the logic? Why pay back early if you care about cash on hand? If you don't care about liquidity or cash on hand then why are you worried about accured interest because you are not going to pay more to anybody but your own self. Further it doesn't matter after you meet FRS, it also doesn't matter because 99% will buy another property after selling away your property.
Just need to keep 1 thing in mind, get more returns than the mortgage interest with your cash and you will end up better. Accured interest is not something the government charge you but is trying to teach you the time value of money, you buy a 1M property in 2014 and sell it for 1,25M in 2024 doesn't mean you earn money, you didn't even break even. That is what accured interest is all about, telling the common people don't be naive, you could have done better by just leaving the money in CPF. Buy a house for own stay, just pump all your OA to pay for mortgage and invest your cash. If you don't know what to do with your cash, you can pay back to OA anytime. Today the money go out from your OA for mortgage repayment, today you can put it back with cash. Even until today, SSB is better than OA interest rate, you can put into SSB and top up OA 10 years later and still be better off. I cannot emphasize enough, do not throw away liquidity, think it over thoroughly and do the maths.