Ann: Suspension from Official Quotation - Annual Listing Fees, page-19

I called NAB and they referred me back to Computershare who are refusing to tell me my SRN, unless I pay a $55 fee for a letter to be sent by snail mail.

I don't think it matters anyway, according to ATO:

If a company is placed in liquidation or administration, company law restricts the transfer of shares in the company. This means that, in the absence of special CGT rules, you may not be able to realise a capital loss on shares that have become worthless unless you declare a trust over them.

In certain circumstances, you can choose to realise a capital loss on worthless shares before dissolution (if you acquired the shares on or after 20 September 1985). This applies if you own shares in a company and a liquidator or administrator declares in writing that there is no likelihood you will receive any further distribution in the course of winding up the company. A liquidator’s declaration can be made after you receive a distribution during the winding up.

I guess that means might have to wait for the liquidator to confirm that there is nothing to be distributed from the liquidation process.