What is the stance of Pepwave / Peplink third party software on their devices?

Does the Pepwave / Peplink end-user license agreement restrict download of additional third part software to a device?

What’s the actual question here? Or the intention? To replace the OS on a Peplink device? Why?
To add an additional app to the running OS? Why?

There are Peplink routers you can run docker containers and full vms on if you want. That would be my approach for any custom requirement.

Not wanting to replace the OS at all. I’m just asking if Peplink/Pepwave has a program that third party developers can enter into for product improvement. In much the same way Apple does it.

Thank you