@David *******
August is about two months away, I recommend waiting for more information. To my knowledge, she will have to cancel the extension of stay based on employment in person, and some roads in Thailand can be bumpy which can be very painful for a pregnant lady. In early August, I would talk to the employer and the doctor and get their advice when she should go to convert her extension of stay based on employment to an extension of stay based on medical reasons.
I also recommend following this group, and the news as well.