How can I program the calendar for an event every eg 3rd Monday of the month?

Unfortunately you can program interval, eg every day, week, every two weeks, etc., there is even a new "custom" setting. But you can't program a specific day once a month because the intervals keep changing.

Not supported in iOS, but it is supported on Mac, so there is hope...

Aloha Rysz.

Thanks for the clarification. Feel like giving it a try? Add an event using your computer, call it it Rysz day, shedule it for every third monday, be sure Calendars is on in iCloud, see if it transfers. Hopefully it does, I've seen this question so often and hate telling the OP they can"t do it. The reason you call it Rysz is after the experiment is done it will be easy to find to delete. Please let me know if it works.

Thank you. Bob.

It works on an iPad too. As it is a monthly event, it can be specified to repeat every third Monday of the month.

Thanks for letting me know it's possible, I found it. You deserve a medal. 🙂

Thank you for your kind words.

You're welcome. I'm guessing this was a IOS 8 change. You'd think Apple could have sent me a memo or something. 🙂

Thanks to picas's and Rysz's prodding I found it's do-able. Can you work it out from the screenshots or need more help finding out how ?

You're welcome. Always glad to help.