How do I subtract days from a date/time field using GlideDateTime in Workflow when task is created?

[vampyre82nd]

I have a requirement to create 21 tasks for different teams, I am using a workflow for this. These tasks all have to be completed at different times, before a set end date. I have read through all the different posting here and have tried most of them to no avail. Is it possible to use a GDT script in the create task script area to subtract days from the u_release_end_date field and then populate the u_release_plan_end field? Or does this have to be done in a business rule?

task.u_release_end_date = current.work_end;

var gdt = current.u_release_end_date.getGlideObject();
gdt.addDays(-2);
task.u_release_plan_end = gdt;

[Mike Patel]

try below in task script section

task.u_release_end_date = current.work_end;

var gdt = new GlideDateTime(task.u_release_end_date);
gdt.addDays(-2);
task.u_release_plan_end = gdt;

[vampyre82nd]

Still does not display in the u_release_plan_end field.

[Mike Patel]

than you might need to change to 

var gdt = new GlideDateTime(task.u_release_end_date);

or

var gdt = new GlideDateTime(current.work_end);

[vampyre82nd · Accepted solution]

task.u_release_end_date = current.work_end;

var gdt = new GlideDateTime(task.u_release_end_date);
gdt.addDays(-2);
task.u_release_plan_end = gdt;

This is what caused it to display. Thank you so much for the help.