The trigger date increments weekly. The conditions date should also.
I enter notes daily throughout the week. The following Monday I want the previous weeks notes sent to X to review the previous week.
You should be able to set your condition to be where Date is in the Last 7 Days (or whatever number of days you want).
Correct me if my thinking is incorrect but then I would need to set up all those requests on Sunday (Saturday?) to capture the entire previous week of Sun - Sat.
Not necessarily. If you want to send it on Monday and grab the previous week of Sun - Sat you could set your condition to be within the last 8 days. You can adjust how many days in the past the condition will look at, and you can include additional conditions if needed.