Hi,
As you know, the App Store approval process can be difficult, but TestFlight Approval is generally a little more straightforward .
I have four apps on the App Store, and two more in TestFlight, a service I've been using since Apple took it over.
As I understand your requirements, you are not asking for further feature development, but you want any necessary changes to make existing code gain TestFlight approval. To confirm the size of this task, it would be useful to have a look at the app code, before agreeing a project.
I develop apps for iPhone/iPod Touch/iPad running iOS 9 and 8, using Xcode, Swift, and Objective-C.
You can see some examples of my work, and client reviews of my completed projects, on my Freelancer profile page (under "portfolio").
It looks like you may be new to Freelancer. Before starting the project, there should be a clear understanding of the details, the deadline, and the milestone payments.
If you'd like to respond to this message, we can discuss things further, before you make your decision on awarding the project.
Best Regards,
- Rob Dixon.