Howdy Valerie,
I would love to help you with this.
That is not yet a feature of our plugin. It would certainly be possible to write a script that does this via WP Cron. But, as of now we do not have such a script available.
If I were you I would vote on this feature request: Delete Past Events Which sounds a lot like what you’re looking for. We have been keeping an eye on that and it is very likely something we’ll build soon, so every vote helps get from here to there. 🙂
Is there a way to export all events , in order to import them at a later time.
There are a few ways to do this. The easiest is probably using the WP Export Tool. That allows you to export any WP Post, including events, for importing into the current or other sites. Your images and other attachments do not get saved locally though, so if you delete those from the server after exporting you will not be able to restore them when you import. If you do not delete them however they should be restored when you import.
Another option would be to download a years worth of events as a big iCal file, but some data can get lost when being converted to iCal.
Does that all make sense? Will that work for you? Please let me know.
Cheers!
– Brook