Ann: Business Operations Update, page-109

they don’t debit the repayment amount until the transaction is due.  So you must ensure you pay the debited amount back onto your credit card when it’s due.

say the first $1000 is taken from the $5000 holding amount..you must pay that when due or else I’m guessing the CC company will start charging interest.  So the way it works is you can obtain/receive your $5000 item of purchase and pay down the amount as it’s due allowing you to manage your cashflow.
 
I believe an app is required to show customers how much money is on hold.  Your current available spend remaining on your credit cards and when payments are to be debited in order for the card holder to seemlessly
manage their spending, credit limit and payment dates.

as I stated previously zipmoney/zippay is like having a credit card with an available limit in the app.  They just need to do something similar to this to allow better management by the card owners.