Hi Chalky,
Please note that the Scarlett series is class compliant, it does not use a driver developed by us and instead uses the Apple Core Audio driver.
Because the Scarlett range is a current product, it will be tested and supported by us for any upcoming OSX versions, even if Apple make changes to their core audio driver. Even when a unit is discontinued (which the Scarlett series is not), we endeavour to support and resolve any bugs with a product for 2 years part discontinuation, please see the following support policy:
http://focusrite.com/support-policy
Hope this helps, please let us know if you have any further questions.
Simon // Focusrite Technical Support