Volunteer Here!
I'm not sure if that is the cause of the error message, but no we currently have no option to do this to my knowledge.
Reloading plugins shouldn't be causing that error message as much as your server specs would be, I would suggest allocating more resources to your server whenever possible if reloading is causing this to happen.
Now if this is just a feature that you would like regardless, you can suggest it on the github.
https://github.com/PluginBugs/Issues-ItemsAdder/issues?q=is%3Aissue+is%3Aopen