A little more research has pointed to this.
If you have your boarding pass, but your checked-in bags are only sent to Changi Please proceed to your nearest transfer lounge/ counter. At the transfer lounge, you may refer to the Transfer Information Passenger Display System (TIPDS) to find out which transfer counter you can request for your checked-in bags to be transferred to your departing flight.
https://www.tripadvisor.co.nz/ShowTo...ir_Travel.html