Changing data source on Access front end

I feel bad asking this, as I am only using an Access front end temporarily, but I have been asked to migrate an access 2007 db to mysql with a php front end. I have moved the data to mysql and am working on the ~400 forms, reports, etc, but want the users to have access to the system while I am developing the new one. I have little experience with access and although I have been able to connect to the mysql tables, the forms don't seem to update their data sources. Is there a way to update the entire access front end to the new tables? Or am I missing something really simple and straightforward. I've googled extensively and I've read all the "similar questions" presented on the page where I am typing this and can't an answer which seems to apply. Thanks for any help or links offered.