There are several churches (8+ a while back) joining in so far and we are expanding to include others. Each church has selected a different day of the month to pray 24 hours for Hawaii (etc). It is up to individual churches how they want to pray. With the custom prayer scheduler (available), it is possible to for a church to have signups for a selected day of the month (eg 31st) or the Nth selected weekday (eg 3rd Monday) of each month. Multiple days of the month are also possible.
Since the writing of the brochure on the home page of this site, Kalihi Union Church (KUC) has had monthly days of prayer on the 30th from September 2017 to now. While the initial time period was 6 AM til 6 AM the following day, they have now opted to pray from 12 AM to Midnight - following the calendar days (since January 2018).
-- KUC 24 Hour Prayer Scheduler (in-house design, currently down during maintenance in transition to new hosting - see note below)
Our scheduler used before that was hosted on the 24-7prayer.com website, with entries included for Jan-Mar 2018.
[ During this transition, (9/25/19), KUC has a temporary signup venue using Google Docs at https://kuc2.monthlydayofprayer.com (signup form) and https://kuc.monthlydayofprayer.com (posted signups manually moderated and instructions) ]