You can't. Once a customer has started a trial with the length you put in LimeLM that's the trial length they're stuck with. So, for those customers, use trial extensions: https://wyday.com/limelm/help/trials/#extensions
Modifying Trial Length
I have changed my Trial Length value for a particular version of my product, but I don't see it reflected on my test PC's installation.What do I have to do to get the new value of Trial Length pushed out to machines that already have the product installed?
I am just starting to incorporate your Trial functionality into my application.I am a very small operation (just me), and I only have one PC (for development) and one laptop (for testing).I am trying to develop and test your Trial functionality, so I need to be able to RESET my testing laptop back to a "virginal" state related to my application in order to execute another testing cycle.How can I delete all knowledge of my testing laptop from the LimeLM servers, so that I can execute another testing cycle?
You cannot reset verified trials. That's by design: https://wyday.com/limelm/help/trials/#verified
To test "clean trials" either use VMs or create new versions in LimeLM and when you're done with them delete the whole version.