To let bygones be bygones is to stop focusing on something that happened in the past, and in this context the speaker is willing to move on until the other party took things too far.
Context: See, I was willing to move on and not dwell in the past till they took things too far.
Hypothesis: See, I was willing to let bygones be bygones till they took things too far.

Given this context, is the hypothesis true (Yes/No/I don't know)?