Although MDIA amendments now require a tabular format for the disclosed mortgage payment schedule and that table can not contain the numbers of payments, mortgage lenders are not excused from calculating and retaining full payment schedules as they have always done. You no longer need the full payment schedule to satisfy Section 226.18(g), but you do need the full payment schedule in order to calculate or verify the Total of Payments, Finance Charge, and APR. There's no way around it.
Not only do you need the full payment schedule, but so will your regulators, investors, litigants, and anyone else who must confirm the accuracy of these three items. If you are unable to produce full payment schedules in one form or another, you will very likely be cited for violations of Section 226.25, Record Retention. Given the regulators' no/low tolerance for APR and FC understatements, retroactive enforcement orders relating to Section 226.25 violations would not surprise me.