So far none. But that does not mean it is not possible.
I feel owners can consider keeping their deeds and enblock only 99 years of their 999/Freehold years to developers will be a good way to unlock their cash in the equity instead of going to banks for loans after their retirement
By allowing this method, the government can then make an equivalent cap on total years for freehold land, say to 1000 years; for those owners that chose to enblock a portion of their freehold title.
Otherwise freehold means forever, and this will help free up landbanks for the country in the future.In this manner, much conflicts in the future can be avoided
rather than making a new policy to control freehold lands, you let the freehold landowners chart their destiny.
for 999 years, there is no issue as the lifespan is limited at 999 years.