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Third hint is coming soon ;-)

Ohhh! Okay I'll see. I thought 2.1 was the third hint and thought you were just taunting me haha! :P

I just realized I made a logical mistake in the hints. Shame on me! The first step that I was talking about is actually the last step of the encryption! Post edited.

OMG. Clever! And I was at some point going "hmm... 4 letters are like nucleotides". Nahhhh that's not it. Cool, I think I know, just now need the right tool...

EDIT: I participate in this challenge (sent by steemit.chat)

Interestingly enough, my strategy of splitting into triplets initially would have worked with one more tweak , but without the hint I likely would have been stuck trying to figure out how to make the missing letters of the code we are supposed to re-encode with this method.