I've looked for hours at other similar questions, but not sure if the other answers apply in my case, and things have changed since I last did this:

I am a sole trader writing an iPad App for an Agency. The app is ultimately for a Company they are working for.

The app will be distributed free to a small number of employees in the Company (<30);

Its a hybrid app, much of the code running as javascript in a webview. Ideally I wish to avoid Apple review of the app during distribution as this is an unknown to me.

I also do not wish to release the source code to Agency nor Company.

What's my best option for distribution? Ad-hoc? Set Company up with an Enterprise account? VPP?

I would use Ad-hoc, as it seems simpler, but not sure what happens after 1 year expiration...

Be grateful for any pointers.