Hi Lindsay,
My organization does pet reunification as well as medical funding. I belong to the Microchip Help group as well.
Although I don't have written procedures, I'd be happy to share with you what we do. But if all else fails searching an outdated chip or tag, reach out to Microchip Help. It's part of the Lost Dogs of America organization. They might have the written procedures for shelters and rescues you are seeking.
https://www.microchiphelp.com/
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Patty Giarrusso
Lost Pet Services, Inc.
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