For sure. Hopefully they have a plan for this and not cut corners.

Did you post this before talking to your builder?

Yes, I will be speaking with them tomorrow.

Tear out wood framing on the right.

Tear out concrete 'ledge' on the left (up to the wood framing).

Re-pour shower pan.

Re-install wood framing on the right.

Thank you all for the replies. The builder contacted me today. They’re going to saw cut, chip, and re-pour the slab as needed.

Should I be worried about the integrity of the post tensioned slab, with this job?

Nah, not for a small area like that.

I'd cut out the concrete on the left and infill under bottom sole plate on the right. Since the bottom plate is floating, if it's a simple partition wall, I'd add a couple of blocks underneath for better support prior to infilling. If it's load bearing, I'd add proper support.

If your shower will have a surface applied membrane on the floor and walls, that'll provide increased protection for the framing regardless of any blocking repairs that are made under the bottom plate.

Sounds like the builder has it handled.

This happened quicker than I expected. Here’s the updated work.

Guessing at a solution can shift responsibility from the contractor even if only momentarily and if only in your mind.