The plan, when I was involved in LW, was to release fry as soon as they emerged. Essentially provide fry to replace the wild spawners prevented from passing above the Landsburg Dam. Have minimal hatchery experience and modification. Since then, I know there was an effort at some short term (1-week or so) feeding to enhance survival.

I think the original law was for something on the order or 30-40M fry (mitigation for 200K spawners). Current releases are a drop in the bucket, but current returns are so small that egg-take is constrained.