If you make a mistake that fits the definition of a GST error when reporting GST, you can correct it on a later BAS that is lodged within the period of review for the period in which the error was made.
However, you can't correct an error to claim additional GST credits when the 4-year credit time limit for claiming those GST credits has expired.
Generally, it is easier to correct a GST error on a later BAS than to revise an earlier BAS. Revising an earlier BAS can also incur penalties or general interest charge (GIC).