They have been "having issues with the suppliers" for months now and considering the popularity of this pistol and all the subsequent configurations I would wholeheartedly recommend fixing the issues with their suppliers.
When I buy a PPQ, VP9, Glock 19, I have all my hand sizes good to go out of the box and if I need to change the size its right there - Sig had the good graces to not only make you spend $45 if you want a better purchase on the firearm, but they have EXTREME supply chain issues with keeping the selection of them in stock - Especially in their most popular size, the Compact.
This P320 is a great pistol, its my first Sig, but months after purchasing it and still seeing threads like this pop up really make me question buying others.
Don't get me wrong everytime I call up Sig they are super nice and helpful, but they really need to work these kinks out quicker.