Combine Cross-String Passages and Fretting-Hand Position Shifts
Sometimes a line played cross-string will also require a fretting-hand position shift. This is particularly true of scales like E minor that use all six open strings. In Example 5, the scale shifts from second to fourth position after the first three notes and from fourth to tenth position at the end of measure 2. These three fretting-hand positions are designated with the symbols FH2, FH4, and FH10 over a dashed line spanning the notes to be played. (As with the picking-hand position markings, these fretting-hand markings are for instructional purposes only.)
Note that the position changes begin on an open string, allowing the hand to arrive at the new position in time to play the next fretted notes.
Excerpted from The Alex de Grassi Fingerstyle Guitar Method