Seems a bug with Payroll entry if salary structure is updated with future date

Step 1: - we created payroll entry let’s say for Oct 1st to 31st. Salary slips are generated (assume salary structure for one staff is X amount). We have not submitted the salaries yet.
Step 2:- We assigned a new salary structure (Y amount) to this staff effective from Nov (1st Nov 2020).

Now we went back to the payroll entry and submitted the salary slips. What we noticed that new salary structure was considered and submitted in the salary slip for Oct 1st to 31st payroll entry.

Please confirm.