How do I know that Cobra HomeBase has already managed the software on my device 8500 PRO HD?
There is no possibility to know if you 8500 PRO HD device has been managed using Cobra, at least not official. However, if your maps are updated, then Cobra HomeBase was used. Additionally, the company emails updates through SD cards, therefore the usage of Cobra is eliminated.
Access the FAQ page to learn more: https://www.cobra.com/products/professional-navigation/8500-pro-hd