Changing Fiscal Periods (from calendar to 4-4-5)

Our CFO/auditors want us to migrate immediately to a 4-4-5 accounting fiscal period system (like end of this month). We have been on calendar periods since we went live on Epicor (over 10 years ago).

I've done this at least 1-2 times with other companies (other ERP systems), and I'm trying to recall/document any issues that came up when making this significant fiscal period migration. If you have done this before, and have anything to share, I'd really appreciate it. Here's some of the issues I remember:

1. Lost (or temporary lost for a year or two) of Last-Year vs This-Year comparison (unless somebody does a manual reconciliation in Excel)

a. GL periods
b. SA analysis/comparison
i. - ERP system
ii. - Business Data Warehouse (Cognos)

2. MRP/Shop Calendar – monthly planning/inventory/forecasting bucket/s definition to change?

Basically, after a fiscal period redesign/redefinition, manual recon had to be done (especially TY vs LY analysis). Or in some cases, custom programs/reports had to be rewritten.

Let me know if you can think of anything else that impacted your companies/departments (and how you had to correct and/or workaround it).

Thanks.
Gerry Mauricio
Klune Industries