Complimentary Alterations with DJ AmEx Platinum

Wasn't sure whether to post this here or in the Clothing/Apparel forum but figured I'm more likely to find other DJ AMEX Platinum card holders here who have personal experience, so hope no one minds.

I've tried googling a bunch of things but can't seem to find information stipulating how to go about claiming the 'complimentary alterations' on clothing (excl bridal) purchased from David Jones using the DJ AMEX Platinum card.
1. Has anyone here used this feature?
2. If so, how does one go about redeeming it?
3. Is there a time limit to have alterations completed in following purchase (provided I still have the receipt to show the item was from DJs, of course)?

1. Follow-up extra bonus points question: Has anyone tried claiming this feature to have a DJs-purchased item of clothing altered after they've cancelled their DJs AMEX? i.e. I have a pair of pants that should qualify for complimentary alteration but am wondering if I can still have it done after cancelling my card (with the receipt proving they were purchased on the card before it was cancelled)..

Thanks for reading. Here's hoping some savvy OzBargainers have the answers I seek!