You can't make a call to webutil functions on PRE-FORM, WHEN-NEW-FORM-INSTANCE, because WebUtil PJCs is not loaded.
But you can use call a non repeteable timer, that calls the code that triggers calls.
You can test the initial time, and a variable to verify if the startup trigger were executed, to avoid some triggers to be executed before the wnfi trigger is fired.
To avoid any interaction of the form with the user,
1) the form can start minimized (without the option to restore and maximize) and restored by code only when the wnfi trigger ends.
2) the items can start disabled and become enabled when the timer startup triggers ends
CREATE_TIMER