What is the legal ruling regarding a prayer area (musalla) belonging to Zayd, to which a piece of land on its right side was added for expansion, and this added piece was lower than the original prayer area by about a handspan or a little more? Does this situation take the ruling of a disconnected row?

A "cut-off row" is one that is interrupted by a barrier, such as a pillar or a wall, which severs the connection between parts of it. If a lower extension creates a gap in the row, it is also considered cut off. This does not, however, invalidate prayer in the prayer area. Worshippers should try to stand close together as much as possible, and there is no blame upon them for what they are unable to do.