Formula for automatically creating a response and fix date and time

[Shirl01]

Hi there,
I need to create a spreadsheet for recording defects so that depending on the defect classification - Sev 1, Sev 2, Sev 3, Sev 4 - then an 'Expected Response Date/Time' and 'Expected Fix Date/Time' can be automatically calculated based on 'Assigned Date/Time'. The Response and Fix times have to be limited to Support Service hours/days which are 9am - 5pm, Mon to Fri.

I'm finding some of the details I need on the forum but nothing that covers the complete requirement.

 

[Shirl01]

Thought it might be easier with the required values:

Classification - Assigned Date/Time Expected Response Expected Fix
Sev 1 - 18/03/2019 10:00 - =(assigned Date/time)+4 hrs =(Assigned Date/Time)+8 hrs
Sev 2 - 18/03/2019 10:00 - =(assigned Date/time)+4 hrs =(Assigned Date/Time)+8 hrs
Sev 3 - 18/03/2019 10:00 - =(assigned Date/time)+4 hrs =(Assigned Date/Time)+16 hrs
Sev 4 - 18/03/2019 10:00 - =(assigned Date/time)+4 hrs =(Assigned Date/Time)+16 hrs

Expected Response and Fix values to be calculated on Mon to Fri, 9am to 5pm