Keep your schedule or your deadlines in a Google Sheet, and see them on your
calendar: kept in sync, with email reminders, even when the sheet is closed.

For bookings (lessons, classes, deliveries, cleanings, rentals, appointments)
and for deadlines (bills, renewals, coursework, tasks): ScheduleRow turns each
row into a calendar event and keeps it in step as the sheet changes. No second
system, nothing to migrate.

- Syncs with the sheet closed: ScheduleRow works from its own server, so edits
  reach the calendar within about a minute, whether or not anyone has the sheet
  open. Rows added by a Google Form sync too.
- Dates from formulas work: let a formula work out the date, filter or sort
  the sheet, and the calendar follows the values.
- Email reminders included: to the people in a contact column, to yourself, or
  both, from 30 minutes to a week ahead, with your business name and a message
  of your own that can include the row's title, time, place and notes. Replies
  come to you. List several addresses in one cell and each person gets their own.
- See it before it syncs: the first sync shows what it will add, and which
  cells it can't read yet, before anything is written.
- Cancel without deleting: mark a row Cancelled in a Status column and its
  event comes off the calendar.
- Safe by design: ScheduleRow can only see and change the calendar it creates
  for your sheet. Your other calendars are out of its reach. It opens only the
  sheet you pick.
- Problems are pointed out, not guessed: a date it can't read is flagged with
  its cell, and that row's event is left as it was. Insert or move columns
  freely; ScheduleRow follows them by their headers.

How it works: open the sidebar, check which column holds what (it guesses for
you), and press Save and sync.

Free for up to 25 bookings a month, reminders included. Pro is unlimited: $6 a
month or $60 a year.