Our bank uses Kirchman as our core processor and this came directly from Kirchman compliance.
"A banker recently asked us what availability timeframes would apply to a remotely captured check deposited electronically into a merchant’s account at a bank. We researched the issue, and finding it a gray area, phoned one of the Reg CC specialists at the Fed in Washington. She said that kind of item is not covered at all by Reg CC, so no availability timeframes apply. A bank may hold it for whatever period it chooses, or agrees to with its commercial customer, or as may be dictated by state law. As far as we can recall, that is the first time a regulatory agency has voluntarily relinquished turf!
The specialist told us that, so far, the Fed has nothing official or written on this topic. There is just an informal, unofficial, unwritten staff position/opinion that they tell anyone who inquires. Their technical regulatory analysis runs as follows: the availability rules apply to cash, which this item clearly is not; to electronic payments, which this item is not because it is not an ACH credit or a wire transfer; and to checks, which this item is not because it is not in paper form when it first reaches the bank of deposit. In her words, “it falls through the cracks of availability.”
As the practice of remote capture grows in popularity with merchants and their banks, we expect the Fed to amend Reg CC to address the availability of such items. If we were betting on how they will decide, we’d bet they will give them the same availability as the original paper items: on-us, local, nonlocal, and so on. That information is in the MICR band data being transmitted electronically to the depositary bank, and can be used to assign availability."