What is the time frame and in what matter must we notify the customer base if we plan to change the withdrawal penalty on CDs are IRAs?

When their current CD matures and it rolls into the new plan.

So we would be fine in putting the penalty language on the renewal notice?

Refer to 1030.5

If I am understanding 1030.5 correctly, it says that any change in terms must be given out at least 30 days before hand if it meets 1030.4(b). 1030.4(b) states that early withdrawal penalty is a disclosure that would meet the 30 day requirement, again if I am reading this correctly. Mr. Carey, we found an ask the guru question that was answered in 2010 that said an increase in withdrawal penalty can be noted on the renewal notice. Our notices go out 10 days before hand. Would this be sufficient?

Keep reading that paragraph:

Alternatively, the disclosures may be mailed or delivered at least 20 calendar days before the end of the grace period on the existing account, provided a grace period of at least five calendar days is allowed.

Ok its coming together now. So it sounds like our period of 10 days would be sufficient on existing accounts since the grace period is longer than 5 days.

If you deliver 10 days before their has to be a 10 days grace period. The pre-maturity delivery plus the grace period has to equal at least 20 calendar days.

I'm going to nitpick for a second and point out to the OP that these accounts being IRAs doesn't factor in to your disclosure requirements. Just focus on the product, which is a CD.

Ditto