The information is gleaned from an internal memo.
Actually the fact that Services 167 and 980 will terminate at
Sembawang Int has been confirmed many months ago, so it's not so
surprising.
As for Sembawang Park, I guess Service 882 will serve there while
Admiralty Rd West will continue to be served by Services 169, 856
and 981.
What's more surprising is the planned extension of either 852 or
857 into Sembawang seemed to not have materialised.
An announcement is expected some time on and around Nov 4th.