Hello
I am currently running a self-hosted installation of Invoice Ninja v4 for my business and am considering migrating to v5. While I have reviewed the official migration documentation , I still have some concerns about the process and potential challenges. Specifically; I am curious about how to handle customizations made in v4 & how they might translate to the new version. 
In addition, I am worried about data integrity during the migration, especially regarding recurring invoices & client records. Are there common issues that others have faced during this transition? What precautions should I take to ensure a smooth upgrade?
Finally, I would appreciate advice from anyone who has successfully completed this migration; particularly with a similar setup (self-hosted). 
Were there any unexpected hurdles / compatibility issues with specific Java server environments? 
I would love to hear your recommendations for planning & executing this migration efficiently.
Thank you !