Google sheets notifications based on dates being reached in cells

General information for the business: internal marketing process
Description of requirements/functionality: We need to create an email notification based on a date being reached in a google sheet (cell) which then mail merges information from the sheet and sends it to up to 5 recipients?

For example I want to use google sheets as a sort of task notifier internally for my team with an email which says:

Hi Janet,

[INSERT CLIENT NAME]'s second marketing campaign now needs researching. It is due out on [DATE] so we have 3 weeks to get the research done.

Thanks,

Mike




We should be able to set it up so we can change the number of weeks/days the reminder is sent out based on a date being hit in the sheet.

We need to be able to set up multiple reminder notifications from one sheet (maybe 300 or so)

Is this possible?

I looked at a an add-on called Reminders but it doesn't let you merge info from the sheet into the body of an email. I also looked at Ultradocs which is a bit more complicated and i'm not sue if it does it or not...

Is this something you can help us set up?

Thanks,

Mike
Specific technologies required: google sheets
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