To edit a timer start or timer end event you've set, choose [Event] from the [View] menu, select the timer start or timer end event (execution-related or access-related) displayed in the detailed information on the timer result on the Events panel that is opened, and then click [Edit Condition ...] on the context menu.

Perform the editing in a dialog box that is opened by this operation.

For details on how to edit in an execution-related event dialog box, see "2.17.4.1 Editing execution-related events".

Also, for details on how to edit in an access-related event dialog box, see "2.17.4.2 Editing access-related events".