...Generally speaking, it is best not to pick at the scabs that have formed. My best advice and what's worked well for me is to gently roll off the dead skin once it has softened in the shower. This seems to work well and actually speeds the healing process along as it removes those patches that want to tighten up and sting when your skin is dry.
I apply Vanicream 30 minutes to an hour following a shower or washing my face with water and a gentle cleanser during the healing phase. It will help keep those scabbed areas softened.
From my experience, the yellow scabs are an indication you are definitely in the erosion phase and ready to begin healing. Those scabs should begin to work loose over the next several days. Focus on keeping them lotioned up as much as you can.
If you have any concerns at all about your stage in the treatment process, don't hesitate to reach out to your prescribing physician or shoot a few pics to him/her with your questions.
I am including a couple of articles about the erosion phase and lingering redness. They may help you in the days to come.
https://skincancer.net/life-with-skin-cancer/efudex-erosion-stage
https://skincancer.net/life-with-skin-cancer/efudex-redness
Wishing you all the best and hoping you get some wonderful results!
April, SkinCancer.net, Moderator