Generally you should be considering a charge-off on/after 30 days. I know of no minimum time. Certainly reasons could dictate that a balance is an immediate loss and you'd be fine to charge it off right away.
As to Reg J, I can't speak on that. The charge off process is an accounting issue, not a "check collection" issue.
My opinions are not necessarily my employers.
Rules and Regs minus Relationships equals Resentment and Rebellion. John Maxwell