Solo 1 uses 3 different Standard Riff type licks in the key of Bb.

The lines in bar 1-4 of the blues progression – on the I-chord Bb7 – use Standard Riff shape nr.1.
They have the tonic on string 4 and 1.

Right before we get to the IV chord we end the lick on the flatted 7th of the chord / scale to signal the change.

Going into the IV chord we’re using Standard Riff shape nr.3, with the tonic on the 3rd string. Play it with your ring finger.

Going back to the IV chord we’re targeting the flatted 7th of the Eb7 to signal that change.
It moves up to the major 3rd of the Bb7 chord on string 1.
Inner logic at work in both cases.

On the V chord we’re using the shape of Standard Riff nr.2, with the tonic on string 5. Start with your pinky.

Play the b3 to #3 of the V chord in bar 9 with your index finger.

This particular lick is fun to play, because it targets the b3 to #3 move in two octaves.
The first one on string 4 and the second one on string 1.

Using the #3 of the next chord as a marker for a chord change is a good way to signal this change.

If you use the #3 of the chord around the beginning of the bar it shows that you know what you’re talking about.
Swings, Jump & Rock & Roll are full of this “playing with the third”.