Here's something I discovered at SIN by accident when an agent walked me to the wrong lounge. It's worked for me several times since then, including sometimes--this is much riskier to try--getting into TPR. Of course, no guarantees and YMMV. First of all, you need an itinerary that includes FC, albeit perhaps on another carrier. In my case, this was served by domestic FC on DL connections on the same award ticket as SQ. When you arrive at the airport, be sure that the SQ agent prints the boarding passes for the flights on other airlines. Most of the time, including in SIN, they will do this automatically. At outstations, you might have to insist. It's better not to try OLCI because then the SQ agents have an excuse to print only the SQ BPs. Sometimes (in particular, for my first experiment), the SQ agent will automatically see the flight in FC and print your BP for that segment on the FC SQ stock with the red banner on top. If not, point out that you of course are not travelling in coach and want your BP to reflect your cabin class correctly. You need to have a fresh SQ FC BP, even if not for a SQ flight. Have all BPs in hand when you approach the KrisFlyer lounge. The agents at the reception podium will look through your papers to find the departing SQ flight, which in this case is the blue-banded boarding pass. If you look confident and like you know the lounge, they'll probably just waive you in. (In fact, they once waived me in and gestured to the first class side when I was departing on SQ in FC rather than leading me to TPR and on that occasion, I just walked myself to the TPR entrance with no problem. When I first discovered the trick, the agent mistakenly walked me to TPR based on my DL FC BP.) In SQ T3, the first class side and the business class food area are the same direction, so look like you're going there, rearrange your BPs so that the FC one is on top, and walk into the FC side of the lounge. You might want to pause on the way to inspect the business class food, which is more extensive than the food offerings on the FC side and can be used also by FC passengers. With your red BP visably on top, no one will challenge you to look more closely at your BPs when you walk confidently into the FC seating area, even if you ask for champagne. If you want to go for broke and try to enter TPR with your documents, this is a much bigger risk and can get you escorted to the business class side by the dragon guarding TPR. Again, YMMV.