Hey BlueSkies!
If the client has paid for the whole mowing season, and they do not require any additional invoices, and you want to ensure they are not accidentally invoiced, I would do a few things.
The first on the job > edit > invoicing frequency > dropdown > select "as needed - no reminders" > update job.
This will ensure that when the visits are complete and/or the job is closed for the season, the job will not go into the requires invoicing status. Then, just to be extra cautious that this job is not invoiced by accident, I would add visible notes on the job, in the internal notes section and/or the job instructions. The reason I suggest the job instructions is that they are the first thing an employee will see when looking at the job.
If you have questions on that, please reach out to our Success Team
888-721-1115 ext 1