Hi, sorry got no notification on your reply.
So your app.jar will be compatible 7.13.0 and up. So also against Jira 8.x (there are some strange things different in AUI between Jira 7.x and 8.x, and some other very special things, but you should be fine)
You have properties>jira.version=7.13.0
When you then run “atlas-package”, the JAR file will be compatible to 7.13.0 and up. But I recommend you to test it on every version at least if Jira starts up with your app installed.
So I would do something like:
atlas-run --product jira -v 7.13.0
atlas-run --product jira -v 8.0.0
atlas-run --product jira -v 8.1.0
atlas-run --product jira -v 8.2.0
atlas-run --product jira -v 8.14.0
At best automated in some CI Server. But you will only need that if you publish your app on the Marketplace. If you simply use it internally in your own Jira, just keep it up to date to the Jira Version you are actually using. So if you upgrade once to Jira 8.14, then some time after you can update your code to properties>jira.version=8.14.0
So it depends
TL;DR: in short, your App is compatible to the minimum version of what you specify in the pom.xml and is potentially endlessly upwards compatibly (unless Atlassian introduces some breaking changes in e.g. Jira 9 or so, which is very very seldom)