The Design Standards (in this case, Part 25, either FAA or EASA) talk a lot about establishing weight limits for which the requirements of the Standards are met. Or, if you prefer, to show compliance with the Standards. To answer the question would need some knowledge of any particular certification program and so on. Not necessarily a simple exercise to establish an answer for any given Type/Model.
It took a little while to get ops to understand that if we could load some ballast we could do it non-stop.
Sometimes you just have to cry a little bit - we can but try .....
Routine loading system restrictions and considerations are in a different basket. For this story, we are concerned with whatever might be the limiting certification design issues ....