Depends on when winter is over, but sometimes even early Feb I have done great fishing spawnng fish. By March there shouldn't be any reason they would not have started in and that is all your looking for. Here if I find them longlining in water from say 71/2' to about 9' of water depth, I know it's on!
That is how I know it's time!

of course I don't know that lake well personally as I Have never fished it. I will see about a guide on that lake for you in a few days from some guys I know fish that area. I have fished Toledo Bend and Sam Rayburn since they opened in th late 1960's and just don't see the need to go any place else, but I will go like to Arkansas for a break and hire a good guide!