Of course you can cancel but is 1000 supercharger miles even worth the cancelling of a $2500 charge and putting another $2500 charge onto a credit card? Maybe, but it would not shock me for Telsa to take weeks to give you back the cancelled $2500 first charge.
They will not transfer the deposit so a cancel and new order/new charge would be the only way and you wait for a charge credit back.
I don't think I would bother doing that for 1000 more miles.
No, I dont believe its worth it... but thats not what that poster said. They said "tesla says there is no way to cancel" which obviously is not the entire conversation. There is zero chance that was the extent of that posters conversation with tesla, which was my point. Of course you can "cancel". What you CANT do is "Transfer". Its likely just as you say (cancel, wait for a refund, re order).. but I dont know... but I KNOW that a tesla representative did not say "there is no way to cancel your oder, sorry".