Update for this one:
i have not physically received the card yet. However, when I log in online and go to the self service > activate cards section I have a new standard account card sitting in there waiting to be activated. Completely new card number. So I suspect when I receive the new card I will be able to make 50 transaction per day on the original standard card, platinum card AND new standard card received when downgrading back to standard account. 150 transactions per day coming up!
Update for those interested:
I received my new standard BW QF debit mastercard today and just activated it. Not in front of a computer so haven't been able to program a macro for this yet however I used it successfully to make a 1c payment at woolies (after already making 50 on my original standard card and 50 on my platinum card today. I will do the macro tonight and try to make another 49 payments on this new card but I think it's safe to say I will now have 3 cards in play and 150 transactions per day going through my account.
Anyone thinking of downgrading from platinum back to standard I think can do it. So as not to arouse any suspicion as to why I was downgrading less than a month after upgrading I told them I decided to pay more off my home loan so didnt have the cashflow to deposit $4k per month.