July is the best month, the water warms up to shorty or even boardshort temp and the wind is most consistent. June can be good too but colder and less consistent. August has consistent wind and it’s warmer but the river flows are lower and there are usually fewer nuking days than July.
I have seen guys prone there on regular boards, but I would think most are moving to dedicated DW boards at this point. One thing that’s important to understand is that the bumps are not consistent up and down the river, there are certain spots like the Hatchery where they form up really good but a mile or two east or west they aren’t as good. This means you need to be able to get up in sub-optimal bumps if you are doing longer DW runs. It also means that the windsurfers/kiters/wingers all clump up at the best swell zones, so be prepared to be surrounded at times and a bright color helmet or rashy is a good idea
I don’t have any recs since I camp at a friends house when I go. It is a busy place these days though so early reservations are probably a good idea.