In P6 Professional, you can import the schedule’s actual start and Finish dates from Excel. But why must I import the Excel spreadsheet's actual start and finish dates twice before the actual start dates are read in correctly?

Let me demonstrate. The P6 Professional schedule I want to update is the below Figure 1.

Figure 1

The spreadsheet, and the actuals I want to import are in Figure 2.

Figure 2

The actual start, original duration, and remaining duration columns define the schedule progress. Note the actual start and finish dates of “Start Project” and “Drain Piping System” in the spreadsheet above. When I import the activities and activity relationships, the updated schedule appears in Figure 3.

Figure 3

The actual finish dates look good, but the actual start dates do not match the spreadsheet. Observe that the actual start of the “Drain Piping System” is June 4, 2025, not June 5, 2025, as specified in the Excel actual start field. In order to achieve the desired actual start of June 5, 2025, for “Drain Piping System,” I have to reimport a similar spreadsheet with the exact same actual start and finish dates, see Figure 4.

Figure 4

When I do I get the following, Figure 5, which correctly matches the spreadsheet actuals.

Figure 5

Again, this time, the actual start dates look correct. But is there a reason I had to import the actual start and finish dates twice to get the actual start dates to read in as appropriate?

Any thoughts?

--Steve