Can we call a screen in MSS from ESS ?

Hi Gurus,

I need to call the Create Substitution page of MSS from the ESS Leave Request Overview Page. We are on NWBC 7.1

The requirement is that the managers, when they try to create a leave request, realize that they have not created a substitution. So they do not want to go all over to the MSS page, then navigate to Substitution rule..... Instead they want a button added in the Leave Overview page of ESS so that they can easily navigate to the MSS Substitution page.

Adding a button is easy, however I am not sure how to call the event. I am trying to add the code in the Class CL_HRESS_PTARQ_APP_CC_ASSIST, by enhancing it, however not sure how to call the MSS screen from here!

Is this an easy development/change with few lines of code? And how to do it?

Thanks in advance.

Regards

Jack