Short answer: Extra payments = permanent reduction. Redraw = take extra back out. Offset = savings reduce interest, keep access.
Extra payments reduce your loan balance permanently. Redraw lets you take extra payments back out later. Offset uses your savings to reduce interest without touching the loan balance. Extra payments save the most interest but you lose access to the money. Redraw gives flexibility. Offset keeps your savings separate but working.
Extra Payment: $10,000 permanent reduction
Redraw: $10,000 extra, can withdraw later
Offset: $10,000 in savings, interest on $490k not $500k
Flexibility Ranking: Offset > Redraw > Extra payments
Savings Ranking: Extra payments > Offset > Redraw