If you were really sorry about something, then you wouldn't do it. If you want to apologize, apologize at once. But don't apologize years later. Because most people find that insulting.
I like apologies...when paired with modified behavior. Human beings are dynamic, not static. What someone wasn't sorry for previously, they might deeply regret now, and I'm certainly not wise enough to see into another's heart. If I can help lift someone's burden of guilt and shame, I'll certainly do so, and leave the adjudicating to karma.
