Default Variations not working properly

Regarding your question “Did you already try creating a complete new feed for Skroutz? Does it get stuck too and does it create fatal error logs?”

1)Yes I tried to create a new (it stucked)
2)No I dont have fatal errors

Thanks for your reply.

Than we are a bit lost though, if your feed would get stuck because of a bug/error in the plugin then it would show in the fatal error logs, if it would run out of memory or experience a time-out then it would also show in the fatal error logs.

All we could think of at this point that it is still related to your cron set-up and the second/third batch never get fired. You mentioned this before:

I have disabled the WP-Cron and I run it with server cron.

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