No, not the hard core expectation, it is now a suggestion.
The hardcore ended in the early 70's.
Actually, there was a required 10 hour quota for publishers up until 1970 or so. There was a quota of 12 magazines/month, 6 RVs (BCs)/month, and 1 bible study/month. They used to post a large chart up by the platform with each month's congregation totals and averages. Congregations were quite competitive and comparing and judging each other. They finally stopped that about the same time.
So the national average is a replacement for that means of juding others by the numbers. JWs would not be appointed as regular pioneers unless they had maintained this quota for 6 months and were conducting 1 home bible study.
When it changed, the talks centered around the concept that now some publishers would do more than the obligated 10 hours each month and that those who could not make ten hours would not be discouraged. Horsepucky. It was to cover the fact that the zeal of the average was waning and putting that info up publicly in the congo was too revealing.
*** km 2/71 p. 3 A Letter from the Pioneers ***
First of all, before you can enroll as a regular pioneer you must have been baptized for at least six months, and during the past six months you must have been a regular publisher reporting at least ten hours and six back-calls on the average each month. You must currently be conducting at least one home Bible study.
*** km 2/73 pp. 1-6 Branch Letter ***
How about congregation publishers? They are increasing in numbers, from 389,555 for the previous year to 401,519 for the first three months of the 1973 service year. That is good to see. But their report of hours is down from 9.9 to 9.6 per month, on the average.
Some have said: But we have no quotas now.? Though the hour requirements for the various branches of pioneer service have not changed, it is true that congregation publishers have no set goal of, say, ten hours per month. Yet the question might be asked: Is this a valid reason for decreasing the amount of time spent in doing the will of Jehovah God in the field service? Really, in past years we were not going in the field service simply to meet a goal of hours, were we? We were interested in preaching the good news of God's kingdom, to magnify Jehovah's name and to give others the opportunity to hear. And we still are. Now that we do not all have a set goal of hours we are not to conclude that our field ministry is any less important. Our message is urgent. This is something to think about, don't you agree? Jehovah's requirement that our service be whole-souled has not changed.
http://www.jehovahs-witness.net/watchtower/beliefs/227881/1/Is-the-10-Hour-Per-Month-Requirement-Still-In-Force
*** w71 6/1 p. 335 How to Succeed in the Pioneer Service ***
It is not easy to jump from a pace of ten hours a month as a congregation publisher to one hundred hours a month on the pioneer track.
*** w65 9/1 p. 524 What Comes First in Your Life? ***
Surely the suggested minimum goal for this, twenty minutes a day, two and a half hours a week or ten hours a month, is a reasonable one for a mature Christian. Jehovah's witnesses try to devote at least ten hours a month to their field ministry
It has been 10 hours from my memory in 1962 and eventually they dropped it.