If you edit the Title Block Block in the Blocks palette, it should change/update all the copies of that Block in the drawing.
My application would not be served by editing the Title Block, as a Block item or not.
Consider the actual number and complexity of the steps between my approach and what is suggested here.
Mine (keep in mind that the portion of the Title Block that is not changed is on a separate, Locked layer):
1) Select All and Copy (two hot keys)
2) Switch Paper space (one button click)
3) Select all, delete and paste (2 hot keys and a button press)
1) Switch to window with the desired text (hot key or mouse)
2) Select and copy the desired text (two hot keys, and maybe a selection move)
3) Switch back to TurboCAD (hot key or mouse)
4) Select the Text item and go into Properties (mouse click and hot key)
5) Select the existing text and paste its replacement (mouse sweep and hot key, because <Ctrl> A doesn't work inside Properties)
Another method occurred to me as I was typing this. I could have the two different text strings on two different Layers, switching their visibility as needed, but that only supports my specific need now, not the more flexible capability I have envisioned for future projects.
TC Pro Platinum 2017, 2016 & 2015 (all with LightWorks) & V21
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