Old site with JEM 3.0.6 on Joomla 3.8. "Upgrade" to JEM 2.2.x?

A customer has a site with a J3.8.x with an old JEM 3.0.6.
To gain security and have an updated site, which version we can use to upgrade JEM?

Thanks a lot

Hi, sorry to send you this information. JEM 3.0.6 was only thought for testing purposes. Then the evolution went in an other direction and the developping of JEM 2 has much more possibilities even for Joomla 3.8 than JEM 3.
There are posts here in the forum, how to export datas and import then into JEM 2. Please search for that

from an older post:
my proposal (after backups) is:
update to JEM 3.0.7, because this only has in settings the button "clean db on uninstall"
go to JEM>settings>global params and choose clean db on uninstall=Yes
export events, categories, venues and catevents from JEM 3 to CSV. Perhaps you have to export images too, if you need them.
then uninstall JEM 3 and all JEM plugins and modules via extension manager, search JEM and choose them.
Then you should be able to install JEM 2.2.3
Perhaps you compare exported files from JEM 2.2.3 with the exported from JEM 3 and adapt.
Then import with replace if ID exists =yes
(if not the categories and venues have other ID, which will create problems.