How is one firm handling AI disclosure and use in engagement letters, and does billing come into play if AI use isn't charged separately?

One member described their firm's approach: they added a disclosure in their engagement letter last tax season stating that AI is used in their processes, since AI is embedded in essentially every service they use. In their workflow, AI is used only as a check—they generate an Excel version of the tax return from source documents using AI, then compare it against how those same documents were auto-imported into CCH via Autoflow. If there's a discrepancy, they investigate. AI is described as an ancillary tool, not a source of truth, and it isn't relied on for actual information. Because every return is also reviewed by a CPA, and AI isn't used for advisory services, this member doesn't believe billing is implicated—especially since the firm operates on a fixed-fee basis and doesn't charge separately for AI-assisted work.