Now that's pretty interesting! I have another Earland album on that very same Choice label, but that one is a trio recording: organ, guitar (Jimmy Ponder) and drums. I think it was recorded in 1966 and always assumed it was his first (pre-Prestige) recording!
I have the Bumble Bee Slim too. Not really hard-edged Chicago blues, but - as expected - blues with a jazzy feel (or jazz with a bluesy feel), more or less comparable with other PJ recordings such as Jimmy Witherspoon (w. Teddy Edwards) and Paul Bryant.