I am quite a newbie myself, but I'll tell you what I would do, and maybe it is a stupid thing, so wait for some expert's answer first!
I would piece all the intended blocks, and then I would have them washed a full cycle in cold water with a bunch of colour catchers, but before I join them together as a top. Maybe if I am afraid of them ravelling I wash them in a fabric sack, like an old pillow cover. This way, if I saw that one of the reds was still bleeding over the neighbouring clear fabric, I would discard those specific blocks and replace them with other blocks that use a safer red fabric. Only when I'm sure of the blocks would I put them together with sashing and borders and quilt them, and then wash the final quilt with vinegar.