This pattern is one of the earliest (seen used between 1962 and 1966). Note that there is some variation in the displacement of the initial part of the "J" as shown in the two versions of the pattern on the left and in the various examples on the right.
This pattern is seen from Gemini (1965) through Apollo (early '69). The first loop is rounded but the loops on the "J" and "g" are progressively straighter on the downstroke.
This pattern is seen throughout the Apollo era and through to the Shuttle era (from 1969 through to at least 1984). Note the rounded "teardrop" shaped loops.