Jakebear, while I may not be the 'go to' person for this on the forum, a possible cause suggests itself. #1, have you ever noticed the same thing on your return jets, before the changeover? (esp the inside of the 'eyeballs'). [I'll assume a 'yes' answer and continue]. You said that "the only real change is the bleach", I beg to differ, another change is that you have been replacing 500 - 1000 gal every other day with well water. What I suspect is that you have a small amount of metal in your well water, small enough to have gone unnoticed with just regular 'top-offs' in the past and now you have increased the 'normal' amount in your pool by purposly increasing the concentration of well water in your pool.
With that said, there is a difference between the different types of chlorine routinely applied to a swimming pool; the concentration and delivery method. I don't know how you've added the dichlor and cal hypo in the past, but I think that it never came in close (concentrated) contact with the areas you now find to be staining. Bleach, on the other hand is usually poured directly into the pool, and I know that when I add it, I pay extra attention to the returns, stairs and suction areas - if you do the same, you have a 'plug' of highly chlorinated water in these areas and high chlorine will precipitate the metal out of the water.
But you asked for a solution:
Take some tap water down to a pool store and have it tested for metals, I truely think you'll find some. If you do have metals in the fill water, always add a sequesterant before adding the fill water (please see the 'stains and metals' section for more expertise advice). I may be way off, but I've given you the best that I can - Welcome to the forum!! - Waste