5d mk IV AEB and Auto Focus off on subsequent shots.

I shoot real estate use AEB for my HDR bracketed shots. I Auto Focus then switch the lens to Manual Focus, to avoid the camera refocusing between shoots. Shoot the brackets shots, then set the MF back to AF and set up the next shop. I've tried using the AF-ON ok for the first shot, but the subsequent shots the camera wants to refocus. Any work arounds besides the manual switch on the lens?

Thanks,

Ron