Greetings,
When you see a support since BIOS rev and that revision is earlier than the one your board has currently, the CPU will be supported since a newer BIOS has backward compatibility.
Caveat. In very rare instances, I've seen cases where sticking with a BIOS rev intended for your CPU generation offers greater stability. Why? Some level of BIOS tuning and variance can exist between different BIOS revisions. A manufacturer might spend significantly more time testing and "tuning" BIOS revs which are being released while a specific generation of CPUs are being sold. Over time, a newer BIOS rev may not offer the same performance when used with an older CPU. This is an optimization process that can sometimes go unnoticed or occurs as a result of testing (or lack thereof) as boards whose sockets might support more than one generation of CPU over the course of its useable service life. You won't need to worry about this with the i5 10400 (comet lake family).
