anything more specific? For example phone or tablet usage? Or easier integration with something? Or even better, new functioanlities in the system that they might like?
Software companies put the vast majority of their development time and effort into their current and future products. If you encounter a problem you have a much better chance of it being resolved if it also impacts product the company is currently selling. Nothing unique to NAV\Business Central. Just the software business in general. You will always be far better off staying within supported versions of any software product.
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