just some thoughts:
-no regulation currently against it, but Nacha is exploring a Nacha Rule that puts the liability to the RDFI if a reversal is sent through and there are no funds available prior to the original effective date
-trying to pick and choose account type or product to get this will be problematic
-requiring sign up will be problematic, think of the effort to add each client independently and how much manual effort that entails
-if you give them credit interest should accrue from that date of deposit/access to funds
-be prepared to discuss with your clients why the last 3 have come on wednesday but today it came on thursday, and why the bank only posting 1 day early instead of 2 made me OD my account (even though i'll assume if you do it you will disclose it it based on when originator sends, but people will forget that part and you'll be the evil bank)
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