Bleach and fix process to completion. You can run this step to process by inspection to completion. Once you see activity start then process for at least twice that time, but at minimum for the time specified with the kit. The difficulty with blix as compared with separate bleach and fix is that there is some danger of retained silver which means that the bleach and/or fix did not complete properly, and a separate issue is the lifetime of the combination which is shorter than for separate solutions. Your colors will not be affected by running the blix for a longer time, and this is probably a good idea anyway when using the solution for several films. For E-6 your clear leader should be clear at the end of the blix.