Change JP domain name update time from once a day to 15 minute interval

I heard that it has already been implemented yesterday from 2 pm on April 3, 2006. This will greatly shorten the waiting time until the domain penetration, so it seems like I started to set up a new site right away or launch an urgent campaign site. Or, there is a reason why it was impossible until now.
JPRS dramatically shortens the JP DNS update interval from yesterday - Japan Registry Service (JPRS) Company Profile
http://jprs.co.jp/press/060404.html

(1) On February 24, based on the results of the stability experiment that we have been implementing since December of last year, we set the effective time on the cache server of the information that "that domain name does not exist" which had been on the previous day as 15 I shortened it to minutes.
(2) We upgraded the DNS software from "BIND 8" on March 22 to a more reliable "BIND 9" in the future.
(3) On April 3 (yesterday), we changed the DNS information which was once a day to once every 15 minutes.

(Note) Due to the convenience of operation, a time zone during which DNS update is not performed is set every day between 3:00 am and 5:00 am.

In other words, we updated this difference for only 15 minutes by updating only the difference. Conversely if it was not a difference until now ...... That one is surprising ... ....