The M.O. at Fat Possum Records sure has changed over the years. Early on, the Mississippi label focused on aged, venerable, black bluesmen like T-Model Ford and R.L. Burnside. But sometime after the Black Keys hit it big around 2005, Fat Possum became a haven for up-and-coming, margin-walking-but-not-quite-marginalized rock acts. Its roster now includes rockers Wavves, Tennis, Yuck, and, with the June release of its self-titled debut LP, Unknown Mortal Orchestra. Although crafted along the lines of garage and indie, the New Zealand-bred, Portland, Ore.-based band's grimy approach shares more with old soul than white-boy blues. Ruban Nielson's falsettofied yelps and mews lead, while his jangly, deeply faded tunes resemble a more conventional, stripped-down version of the Go! Team. So is this a recycle or a revival? Decide for yourself when Unknown Mortal Orchestra opens for Yuck on Tuesday, July 26, and Wednesday, July 27, at the Independent.