Hi Trisha,
There are different dates. When work order will be generated will be governed by Earliest Next Due Date.

When you generate PM work Order start date will be Target Start Date and End date will be Target End Date.
Target Start Date:
- Time-Based PMs: For time-based PMs, the Target Start Date is calculated by adding the PM's lead time (defined in the PM record) to the Earliest Next Due Date. The Earliest Next Due Date is determined by the PM's frequency and the last completion date of the previous work order.
- Meter-Based PMs: For meter-based PMs, the Target Start Date is calculated similarly, but the Earliest Next Due Date is based on meter readings and the PM's frequency.
Target Finish Date:
- It is based on the Target Start Date and the estimated duration of the work. If you don't have Duration defined on Job Plan then Target Start Date = Target Finish Date.
Hope this clarifies.