Watch the Level 5: Blues Chord Melody online guitar lesson by Jason Loughlin from Take 5: Blues Chord Melody
This etude is over a 12 bar blues in A. In the last four bars, we're playing the V chord for the first two bars. There is no V|IV progression in the last four. The turnaround is just a V chord. To recap, the last four bars will sound as this V|V|I|V.