Hi robert-sloan,
Thanks for reaching out. The system is designed to record any changes that are made after a BAS period is lodged. These will be recorded as amendments on your next BAS.
If these amendments do not need to be reported to the ATO you have the option to unlodge and relodge the last BAS to move the 'changes' back into the correct period.
If these changes are legitimiate amendments and the ATO needs to be notified, this will be done via lodging your current BAS period as normal.
Please reach out to the Support Team for further assistance if required.
Thanks,
Rebecca