migrating to a different joomla site

Hi, I need to migrate the easyblog site I have to an already established joomla site. Both already have a set of users in their databases.

I read your article about migration here: https://stackideas.com/docs/easyblog/administrators/migrations/migrating-to-a-different-joomla-site

and I noticed the point "Migrated all users from the original site into the new site. All user ids on the new site needs to be the same as the origin site"

If I use a user migration tool, I think they will create new user ids for the blog users being migrated. What will happen if the user ids on the new site don't match the origin site? basically how do you recommend the users be migrated?

Thanks