Hello. We have plan to upgrade Pega platform version 7.1.8 to 8.3 on productive environment, where installed many applications, but on version 8.3 should leave (keep working) only one. This application works in high-availability mode 24x7. For such upgrade it would be better to know answer on following two questions: 1) Is it possible to restrict upgrade Pega platform procedure to exclude rules from unused applications (upgrade only one application)? 2) After migration the application could we find any solution to load its work object instances from previous version (7.1.8) to new one (8.3)? Thanks in advance.