Start Time and End Time Auto Compute , Initial Value and App Formula

[Michel_LeBlond]

It is easy to have the End Time auto populate to an hour after the Start Time when a new record is being added.
Setting Initial Value to [Start Time]+ 1 does the trick.

Is there a way to do this for Updates to records so that the new Start Time moves the End Time forward an hour ?
Using App Formula move the time but locks the End Time and makes it non editable

[Marc_Dillon]

You’ll want to use Reset On Edit for this.

[Michel_LeBlond]

Thanks Marc.
Setting the value to true did the trick.