This one is easy ... ALL MACAWS WILL TEST THE BOUNDARIES OF ANY NEW RELATIONSHIP! Plain and simple! Also ALL MACAWS LUNGE when they are testing their boundaries ... they do it in the wild with other macaws, and they do it with their humans. What you are dealing with here is a Mac who learned that he could bite you early in your relationship, and now it's working to his advantage.
*BAD NEWS* You failed the initial test, you are now dealing with the fallout of that.
*GOOD NEWS* You can reverse this, it's not going to be quick, it's not going to be easy ... let me offer you some advice as I see an issue with the way you are handling this situation.
You say that you are "redirecting" the biting behavior ... though this is good, it is not the right idea ... you don't want to "redirect" this behavior, you NEED to eliminate it! That's the first thing, you are doing the right thing by putting him back in his cage ... that, or put his feathered butt on the floor, instantly! An audible "NO" and *boom* on the floor or back in the cage and TURN YOUR BACK ON HIM! ... let him scream, let him call, let him cry DO NOT give him any attention what so ever ... YOU MUST BE CONSISTENT WITH THIS FOR IT TO WORK!
Something else that I see that could potentially be an issue for you, you need to look into "bite pressure training" your mac ... a mac that is properly bite pressure trained is an amazing thing ... you shouldn't have a mac that is breaking your skin, or leaving bruises or blood blisters ... this is an UNACCEPTABLE BEHAVIOR and shouldn't "come with the territory" of owning a MAC.
I also have at my disposal a training regimen for biters ... biting behavior modification if you will, let me know if you are interested.
Big macs are great birds, I would also argue that some are better (B&Gs, RFMs, GWs, Military) than others (Severe and Scarlet) to handle but these guys take a lot of time, work, love and commitment to properly train, but once done can be the most rewarding to work with!
Hope this helps, if you need more info, let me know!
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