Bad support on the PRO plugin

In my case the import and export processes came with an issue. A strange one, to my experience. I have scheduled Cron jobs, but the imports/exports sometimes do what they are supposed to, sometimes not. I am not changing any parameters, so I am thinking that this may have something to do with intervals, iterations, Cron processing time limit, or something like that. It is above my understanding.

Nothing bad here, this is why debugging is for. After doing everything I could (deactivating other plugins, reading documentation, contacting my server etc, naturally, I contacted support.

I have provided a staging environment and admin access to website and FTP, they said that they resolved the issue, but they did not.

What is frustrating is that the communication is below par. They send an email (that does not help), I reply immediately and then I have to wait 1 day to hear back from them. And the cycle goes on. I need 24 hours to wait, before trying again to debug myself. If I need to clarify something on their replies, I need to wait a day again for their answer.

By the way, each time I speak to a different agent and getting a different solution.

I am trying to debug myself and I have hired a developer to consult. But, at this point the issue remains unsolved.