This block likely represents the eastern end of the line of an E-W wall extending west from the northern end of ashlar wall 5765. As mentioned elsewhere, this block seems to have been worked to leave a gap in the wall to the west, before the line of the wall is resumed by 5767. The nature and purpose of this gap is, for the moment, uncertain: possibly it is a threshold or entrance into the small courtyard from the south, mirroring in a way the threshold at the northern end of the courtyard across from it (SU 5740). The nature of the space to the south in Room 20, especially in its original phase, is unknown, and requires further investigation.