This is either the cherry on top tune-up before a race block... or the, "I want to do well in this race in 4 weeks and haven't been training," tune-up.
While this is a much better boon to the former, it is never the less a nice, targeted plan to y=give you a temporary kick.
Purpose: Up-regulate/stimulate/train up the anaerobic contribution to efforts by blending Extensive Functional Reserve Capacity, FRC, Efforts with Max Aerobic, MA, work. These adaptations train up quick, over about 5-6 workouts, and down-regulate quick, about 3-4 weeks. This is the icing on the cake that is the base, mid-intensity, and FTP work we’ve done. This gives you that extra gear. By the end of the block the top end of MA / Low FRC RPE should drop. You will feel stronger.