The other "feature" I've seen with SQ is that often the forward leg will be more expensive but when you look for a return it may be 0 additional cost depending on the day of return! If that return date doesn't suit, assuming you travel in the region frequently, you can take the return fare and park the return for a date change when needed and find a cheaper return leg for the day you require. Yes, most of the fares are changeable at no cost, at least in my experience over the past 18 months or so since I started looking at SQ.
Gne