The IBM3151 terminal emulation has an insert mode that allows the host system to place text anywhere on screen, shifting all other characters on that line to the right. It can also send a Delete character (ASCII 127) to delete the character at the current cursor location. This shifts the remaining text on the line to the left.
Currently no Century Software, Inc., product handles this appropriately. Instead, they display the “small house” character at that location, throwing the alignment for the line off.