How can we setup both monthly and weekly frequency periods with overlapping dates?

Summary: EPM ARCS Periods Setup: Unable to create different frequency periods with overlapping dates (mnthly/wkly)

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Trying to setup Periods in ARCS. Base calendar created as Monthly frequency Periods. Also created new Weekly Calendar for weekly frequency, which will obviously have overlapping dates with monthly.

We get overlapping dates error and cannot create separate weekly periods. Allows us to add Base and Weekly calendar to monthly period, and will create 1 monthly and 1 weekly reconciliation, but won't create the additional 3 more weeks of recons after the first week.

How can we setup both monthly and weekly frequency periods with overlapping dates?