every year harvey norman does this deal, CIS has changed so if customer cancels within 120 days, they have to pay half of remaining ($828 + $500)
Cancel method would be stay on for 4 months and cancel as $69x4 + $69/2x20 will work out to be like $966 all up for flip 7 and $1965 for fold 7.
i prefer to stay on for at least 12 months as i do make use of the data.
remember its advertised instore only
Quick tip - complain to Optus live chat you have bad coverage (even if you don't - (profanity) em), they will give you 50% off your SIM plan (69 x 0.5 = $34.5) for 12 months.