Maybe a little flat around the area, but that is a judgment call. I prefer not to leave an area flat if I don't need to. If you are concerned, just a bit flat, otherwise tiller right thru it. At that length, you should be fine. Again we are talking about knots on the belly. This one is a knot on the belly, but also a knot on the back which is different. Knots on the belly, ignore them for the most part. Knots on the back have to be taken into account. Wider around the knot, leave flat if you have to. Flawless back around the knot.
Remember also that thicker wood wont bend as far as thinner wood. It will take set or break. Breaking will be what you need be concerned with because of the knot. That is the reason I mentioned thickness taper earlier. My opinion, you don't want a big gob of extra wood tucked up inside that knot. The extra width should ideally be the modifier giving you more wood AROUND it. Having said allllll of that, this looks like a non issue at that length and it being close to the tips. Just trying to give you food for thought.