IFS officer usually retires in the age of 60 years although there can be extension procedures as per the foreign ministry guidelines if the officer will be helpful for any situation in building strategy of the nation. Such extensions are a maximum of 5 years.

Now if you want to know about the work duration during the service period then it depends on the situation and international relations with the country you are in. For any emergency situation the working hour may increase, but in general IFS officers usually work for 7-8 hours depending on the work load.

TO know more about career as an IFS visit the link below:

https://www.careers360.com/careers/indian-foreign-service-officer

To know more about UPSC CSE visit the link below:

https://competition.careers360.com/exams/upsc-civil-services-exam

I hope this answer helps. All the very best for your future endeavors!