The timestamp of your converted files will be set to the time and date at which you convert the MSG files.
So, if your EMAIL.MSG file dated Jan 1, 2004 is converted on Jun 1, 2019, the EMAIL.MSG.EML converted file timestamp will be Jun 1, 2019. In some cases, it could be desirable to have the actual timestamp of the converted EML file reflect the timestamp of the message itself.
For instance, you could then sort by date using the Finder.
We have a beta version of this feature available for power users who want to try it. Please contact us if you're interested in this feature, we can provide instructions on how to enable it.