Do you know exactly how often these reminders from Facebook were sent out after the initial request?

The 'REMINDERS' you were receiving from yourself, how often were they automated and sent to you? Was it random? Or was there a pattern? I'm curious because I did receive one from someone on my birthday and wondered if they purposely sent the reminder. I'm shy, so I don't want to ask them directly (I know that you can manually send them as well). This person had me in their pending friend request from 2 years earlier, so it's possible they sent the reminder on purpose. Plus, I received a second one from them 15 days later. Curious if to see if there's a "schedule" to these reminders. Thanks!

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