No, the Ultra does not have a TV tuner, so it in no way interacts with the TV tuner. A Roku TV supports pausing and rewinding live TV when a USB drive is attached to the TV. But there's no way an external player such as any Roku, Fire TV, or any other streaming player could do so.
I will throw one caveat at that: if you have a networked tuner, such as a Silicon Dust HDHomeRun, the channel SD offers for Roku devices does permit that I believe. But I think it requires adding a hard drive to the network tuner. I have such as tuner on my network, but I don't tend to use it for direct OTA viewing. I instead have it linked to a home theater PC and use it for OTA recording. Therefore I don't have a hard drive connected to mine, since the HTPC handles all of that.
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