I just checked and there is programming on channel 551 - BBC First. 9-10am PDT - Antinques Roadshow.
Note that this is a channel rebrand from HIFI to BBC First - so the logo may show up as HIFI depending on what device you're watching on.
It looks like BBC First was placed into a different theme pack than HiFi to better align with the content offering. There are more details here. You can always swap your theme packs or add an individual channel a la carte.