My first visit to the lounge was a bit all over the place, and I nearly got left behind!
Leaving LHR was completely smooth. A porter met me at the car and checked me in, and boarding was fine, etc.
But then not having been to Singapore in ages, it took me a long time to find the lounge in the first place. There were two hosts checking boarding passes at the door, and most people were then directed to the lounge desk, where presumably they were told their boarding times and gates for their next flights. But when my host saw my F/P1 boarding pass, he took me straight into the lounge offering me a seat in the main area or the dining area. I said I was looking for a shower, so he walked me there, and the attendant gave me a free shower room straight away. It was all so fast that I practically had to run to keep up with him.
As I was getting undressed, I realised I had no idea what time or gate I had to reboard at. So there I was half naked checking departue times on my mobile phone to make sure I was going to have enough time to shower.
I made it out of the shower and then would have been completely lost in the packed lounge if I hadn't heard about the reserved area. I asked where it was, and was taken there and offered a drink, and I started doing some work. My seat neighbours (about 30cm away, given how close together the chairs were) had been sitting in front of me on the flight to SIN, and silly me, I just assumed we were all getting back on the flight to SYD together. I didn't hear any boarding announcement around when I thought it would have been based on my shower browsing, but I assumed it was just running late. Then after a while one of my seat neighbours asked the other what time boarding was. About two hours to go, he said. Gulp, I realised they were going somewhere else!
All the waiters had disappeared of course, and I looked everywhere for a depature screen, finally locating the single screen at the entrance (that I would have seen previously I guess if I hadn't been running to the shower). The flight had naturally closed by that point, and it was a 10 minute walk to the gate.
I was the last person to the gate, and they basically shepherded me on board, with all the gates and doors closing behind me. All this was without a single page or call to try to locate me, so I don't know what they would have done if I hadn't appeared.
Of course, all this is completely my fault, and now I'll know what to do on the return flight. But it does seem like with a lounge that big, they could have a few more screens or call the flights or provide a more consistent experience like the example posted previously where the waiters let you know when it's time to board.