spotted references to both the white 16GB and 32GB versions of the iPhone 4 in AT&T’s Online Account Management (OLAM) system.
The OLAM system doesn't say just when the white-colored iPhone 4s may be showing up. However, it does tend to discount speculation that AT&T's spring launch for the white iPhone 4 was not a dodge intended to delay things until they could just axe the white iPhone 4 entirely.
However, the white version of the iPhone 4 is showing up so late one would wonder why anyone would buy it. It might be better to just wait until the iPhone 5 shows, a few months later. This argument has similarly been used as a reason to skip the Verizon iPhone 4, waiting instead for the Verizon iPhone 5.