How can I change onlyOnWeekday(day) with weekday from Google Sheets?

I can make this example example work. What I need is to set the weekday from a cell in column "weekday".

I have tried this:

if(type=='PD'){
  var recurrence = CalendarApp.newRecurrence().addWeeklyRule().onlyOnWeekday(weekday);
  event.setRecurrence(recurrence, tstart, tstop);
}else

...where weekday refers to column "weekday".

What am I doing wrong in my own version?

I could confirm that from your script and shared Spreadsheet, the values of NewWeekday are WEDNESDAY and MONDAY of the string type. In this case, how about the following modification?

From:

var recurrence = CalendarApp.newRecurrence().addWeeklyRule().onlyOnWeekday(weekday);
event.setRecurrence(recurrence, tstart, tstop);

To:

var recurrence = CalendarApp.newRecurrence().addWeeklyRule().onlyOnWeekday(CalendarApp.Weekday[NewWeekday]);  // Modified
event.setRecurrence(recurrence, tstart, tstop);

References:

• Enum Weekday
• onlyOnWeekday(day)
• setRecurrence(recurrence, startTime, endTime)

If I misunderstood your question and this was not the result you want, I apologize.

Added:

• You want to use tstop as "until".

For this, how about the following modification?

From:

var recurrence = CalendarApp.newRecurrence().addWeeklyRule().onlyOnWeekday(weekday);
event.setRecurrence(recurrence, tstart, tstop);

To:

var recurrence = CalendarApp.newRecurrence().addWeeklyRule().onlyOnWeekday(CalendarApp.Weekday[NewWeekday]).until(tstop);  // Modified
event.setRecurrence(recurrence, tstart);  // Modified