Testing / Sandbox for API Users

While the pending / testing / publishing cycle works ok for minor edits, If one uses the DISPATCH API and introduces new fields to be populated and PULLED by the API, then this testing is not sufficient in that you can only dispatch to the PUBLISHED version and not to the test version.

Ideally, I would prefer a SANDBOX (perhaps limited to "X" submissions and X users per sandbox life) wherein I could test the full API activity on my next form version.  Also, if the SANDBOX could be linked to it's own Paypal / Gateway account that would be great.  That way, production could continue while other payment fields were evaluated.

Currently,for a company that operates 7 days a week, My window for updating a form is between 9PM and 6:30 AM.  I'm pretty good, but this takes Agile development to a dangerous level.