Multi column dataload rule

We are encountering issues while loading Multi column datafile with Daily sales data.

1. Day value in the input file :2024245--> leads to FY24 and Day245

Working successfully:

1. Created period dimension with Period classification & Year dimension as Year classification.
2. In the period mapping ,Period name : 2024245; Target Period:Day245,Target Year:FY24
3. Added Period in the import format.
   After doing these changes data started loading successfully

However in the above design , start & Endperiod have to be passed dynamically .They may be should ensure periods in datafile matches with start and end period. Ongoing maintenance of adding period mappings continously.

So we thought of doing the following changes in the dataload