How to I bulk modify working days in JIRA for a group?

[Taylor Smith]

Hi - 

I have an IT ALL group that I need to modify working days for (i.e. company holidays).  I do not want to change the work days for all the individuals in my JIRA instance, just that group.  In addition, they do not belong to a single board or project.

If I write a JQL filter and create a new board on my personal account, and change the working days there, will it have a trickle down effect to all of the other boards the individuals are working on?  

Is there a different/better way to do this?

Thank you.

[Rast]

Just to add to this, i'd be interested as well although for a different reason.

I currently have the prospect of having to add all the UK National bank holidays to 30+ boards manually is somewhat unappealing. 

[Dimitry Proshak]

I'm trying to figure out a similar issue of updating working days in batch due to our teams being spread across three countries and a multitude of boards.