Updating Custom Library Activities

Hello everyone. We have 18.4.5 orchestrator, studio and robot. We created a custom library and still improve it. The issue is that when we updated and published the library, activities (premodeled xaml components, not custom-coded activity) which are not modified (left same as they are in previous version of library) do not work properly in model run and they are needed to replace with new ones in the new package. Is it what the design is? Or is it a problem?