Multiples of Brunei 1973 Second Series Specimen Banknote ??

This specimen banknote A/3 000000 was recently acquired from a Malaysian collector, don't know whether it was from the set which came from a 1995 Spink auction in Singapore:

Extracted from Spink Singapore Auction catalog of June 1995

  Coincidently, my newly acquired specimen banknote also matches the template banknote in prefixes and serial numbers with Steven Tan's latest 19th edition catalog and goes all the way back to my first catalog from him, the 8th edition from 1987:

19th Edition

                                                                           8th Edition

 Extracted from the Standard Catalogue of Malaysia-Singapore-Brunei Coins & Paper Money with kind courtesy and permission from Steven Tan.

Question: Are there multiples of these type of Specimen banknotes bearing the same prefix with zero numbers? Can anyone help provide the answer?