The GB are saying that the FDS will recieve their appointment over all of Christ's belongings when he returns, which is in the future. However they have been saying that the 144,000 have been recieving their heavenly reward since 1914.
W10 7/15 pg 3-7
"Read2Peter 3:13. The “new heavens” is God’s heavenly Kingdom, which was established in the year 1914 when “the appointed times of the nations” ended. (Luke 21:24) This royal government is made up of Christ Jesus and his 144,000 corulers, most of whom have received their heavenly reward."
From the Annual Meeting Report
"Consequently, Jesus will reward “the faithful and discreet slave” by resurrecting the individual members of that group to heavenly life and by giving them royal authority over all Christ’s belongings in heaven and on earth. This is the same reward promised to all faithful anointed Christians.—Luke 22:28-30; Revelation 20:6."
So this reward is being given to individuals prior to it being given to the FDS on Christ's return when he will then give this reward to the individual members of that FDS group. No wonder it is confusing.