Calendar Change from 4-4-5 Quarterly Periods to Monthly Calendar

Our client using Oracle EBS R12 was acquired and needed to change from 4-4-5 Quarterly Periods to Monthly Periods.  They were keeping the same year end, but this was needed to be done 3 months into the current year.  This required using our Calendar Change Software Package to update the last 9 months of the year to end each month, instead of 4-4-5.  We used our software to update the current period as well as all future periods.  We did 2 tests and then migrated it to Production.  The elapsed time was 2 weeks.  This also included updating the Oracle Projects Calendar.  The Fixed Asset Calendar was a separate project as we were also updating the Prorate Codes as well as the periods.