Dispatcher would cache content and Installation of Service Pack or newer forms package should not affect the content. I have done Service Pack Upgrade in my project twice in the past and I can confirm that we did not face any issues because of old content cached in Dispatcher.   

We are migrating from On Premise to AEM Cloud. We noticed that while creating a Form fragment, we are not able to add custom AEM components to the Fragment. We can only add OOTB form components. Also the designs are getting stored under /libs/settings/wcm/designs/fd/af/default. We tried overriding t...