You could create an ACF/Save_post filter that runs both before and after acf. In the first run, het the current values and store it. In the second run compare the new value with the stored value. If not the same then send an email t the site admin.
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2022 was a big year for Advanced Custom Fields, with more capabilities, a new generation of ACF Blocks, a refreshed UI, and a new home. Our year in review post looks at advancements we’ve made and offers a glimpse of the future. https://t.co/HahJUCcyH4