I have fished this lake several times in the past. In fact I am headed there next week to fish on the full moon which I have found to be the best spawning perid overall. Of course all this can change with weather or water levels. I can remember going down there around this time several years ago and having fishing you could only dream about ( 100+ days with many over 7 and 8)only to return the next year and struggle to catch a limit during the same time.
My advice is any where from Jan through March is a good time with the variables of lake levels and weather patterns really more of a factor to contend with.
I love the lake and would highly recommned it but it is not as easy as a trip to El Salto or Hiutes and certainly more unpredicatble. I keep getting drawn back by the wildness of the place as well as the chance to catch a real monster.
If I can help in any way let me know.