Prevent Ship By on non-working day in SO Entry

Is there a way to prevent a user in Sales Order Entry from entering a Ship By Date on a non-working day? I tried to alter the only Calendar created (Which is linked to all possible Calendar associations that I can think of in the system: Company Configuration, Resource Groups, Site Level, etc.) to include working days as M-F but I’m still able to choose a date that falls on a weekend within SOE.

Am I on the right track and simply missing something trivial?
Any ideas?

This would require a BPM or screen customization. I’ve done it before via BPM… if the user chose a non-workday the BPM would change it to the next workday. This was in E9 probably 6 years ago.

Look at:

&

https://epiusers.help/t/adjusting-for-holidays-weekends/44599

This is a wonderful BPM @hkeric.wci. We use it to do just this @Sam_Bise.