See who's due a rebook this month with a colour-coded sheet

Help me build a "who's due" sheet so regulars get rebooked.

My business: [what you do]
Services and how often they're due: [e.g. boiler service every 12 months, dog groom every 6 weeks]
How I contact customers: [e.g. text, WhatsApp, email]
How far ahead to remind: [e.g. 2 weeks before]
Customers who've said they don't want reminders: [I'll mark them]

Ask me up to 3 short questions first if anything important is missing. Wait for my answers.

Then:
1. The column layout: name, contact, service, last visit date, interval, next due, status, reminder sent, opted out.
2. A formula for "next due" from the last visit date and interval, in Google Sheets.
3. A conditional formatting rule that colours a row when it's due within my reminder window, and another when it's overdue.
4. Two short reminder messages (first nudge, and a second one if there's no reply).
5. A monthly 10-minute routine for working through the list.

Add a simple opt-out line to each message (e.g. "Reply STOP if you'd rather not hear from me"), and only message people who haven't opted out. Use only what I've given you, leave blanks for any price or fact I haven't given, and don't invent anything. UK English.

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Help me build a "who's due" sheet so regulars get rebooked.

My business: [what you do]
Services and how often they're due: [e.g. boiler service every 12 months, dog groom every 6 weeks]
How I contact customers: [e.g. text, WhatsApp, email]
How far ahead to remind: [e.g. 2 weeks before]
Customers who've said they don't want reminders: [I'll mark them]

Ask me up to 3 short questions first if anything important is missing. Wait for my answers.

Then:
1. The column layout: name, contact, service, last visit date, interval, next due, status, reminder sent, opted out.
2. A formula for "next due" from the last visit date and interval, in Google Sheets.
3. A conditional formatting rule that colours a row when it's due within my reminder window, and another when it's overdue.
4. Two short reminder messages (first nudge, and a second one if there's no reply).
5. A monthly 10-minute routine for working through the list.

Add a simple opt-out line to each message (e.g. "Reply STOP if you'd rather not hear from me"), and only message people who haven't opted out. Use only what I've given you, leave blanks for any price or fact I haven't given, and don't invent anything. UK English.

Stay in this Copilot chat. Leave plugins off, and do not open a file from OneDrive.