@pipoulito That is the format ACF stores dates. You should contact the developer of Revolution Slider to figure out how to use ACF fields with their plugin. I can tell you what’s ACF stores for a field but cannot help you use it in the other plugin.
Date fields should be sorted either as numbers or text, but not as dates.
@ryanacarty yes, Rev Slider is a commercial plugin that requires a license to update. Some themes package it and include it but not of them include a license for this plugin.
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