I hired a contractor who made a big mistake. He installed a ceramic floor onto 1"inch cement board (that is screw into welded beam constructed subfloor). He did not use thin set or tape over the seams in the cement board. I was able to take out all the ceramic pieces however the mortar is completely glued to the cement board. It would take a month to take out the mortar. I see small cracks in the mortar where the cement board seams are.
What would be the best way to reinstall the ceramic without have to spend a month or more chipping away the mortar?