Field help (FLGMODBP) 

Select this check box to modify the BP account number according to the following next options:

Select Shorten or Lengthen.
Select whether to add or remove characters from the Right or Left.
Enter the number of characters to modify.

If the character length of the BP account is less than the number in the entry field, zeros are added to the account number.

Modifying BP account numbers is only effective for BP accounts that have not been assigned to a DATEV BP account in the DATEV BP account assignment function.

The length of DATEV G/L account and BP account numbers are interdependent and must follow these rules:
DATEV G/L account numbers must be between four and eight characters long and must always be one character less than the DATEV BP account number.
If the G/L account number is eight characters long, the BP account number must be exactly nine characters long. 
DATEV account numbers (G/L account or BP account numbers) must always be numeric.