@asmecher Sorry for posting an illegal mix of collations question here. But firstly,
I started implementing the solution offered in this post by @Dulip_Withanage, so as a follow up I continued with the same thread to update on what happened after the solution implemented.
Your quick reply and lead ( DB Error in OJS 3.2.0.0 - an illegal mix of collations) helped me to solve my database issue. I have changed database, tables /columns collation to chf8_general_ci and I can schedule the publication now.
I have another question but I 'll post it in another post.
Thanks once again for your support.