Hi Marcelo,
Sorry for the late reply. The reason there are two places to enter a start and end date are due to the differences between creating the series and the individual occurrences.
When you first create the work order, the Ddue date start and end dates are in reference to the original occurrence, as if it was a one time occurrence. When you mark the work order as "recurring", the dates you are entering there are for the length of the series.
Using you example, you would set up a work order to be done from 11am to 12pm on this coming Wednesday. This date and time is setup at the top of the screen. When going into Recurring Dates you are now setting up how often this is set to occur. Here your start and end dates would be when the first occurrence is supposed to start and when the last occurrence is set to end. Therefore, for a yearly occurrence, you'd want to make this end date many years in the future.
For the renewal process, this is merely a flag to remind the user to renew the occurrences. In the Existing Work Order list, there is a dropdown filter view for work order that are set to be renewed. You can then select those work orders and renew them in the "Update Selected Work Orders" tab.
Hope this helps,
- Adam