Help me understand an Ampeg SVT schematic

[g1]

I just realized the schematic in the first post is a piazza drawing which may or not be accurate. I prefer to always use the factory drawings.
Here is a link for the factory service manual. The parts list states that the ultra-low and the 2 ultra-hi switches are all the same part number.
https://music-electronics-forum.com/...4&d=1542072839