diff --git a/common/script/cron.js b/common/script/cron.js
index dba2a13717..2de430e73b 100644
--- a/common/script/cron.js
+++ b/common/script/cron.js
@@ -47,3 +47,24 @@ export function startOfWeek (options) {
   return moment(o.now).startOf('week');
 }
 
+
+/*
+  This is designed for use with any date that has an important time portion (e.g., when comparing the current date-time with the previous cron's date-time for determing if cron should run now).
+  It changes the time portion of the date-time to be the Custom Day Start hour, so that the date-time is now the user's correct start of day.
+  It SUBTRACTS a day if the date-time's original hour is before CDS (e.g., if your CDS is 5am and it's currently 4am, it's still the previous day).
+  This is NOT suitable for manipulating any dates that are displayed to the user as a date with no time portion, such as a Daily's Start Dates (e.g., a Start Date of today shows only the date, so it should be considered to be today even if the hidden time portion is before CDS).
+ */
+
+export function startOfDay (options) {
+  if (options === null) {
+    options = {};
+  }
+  let o = sanitizeOptions(options);
+  let dayStart = moment(o.now).startOf('day').add({ hours: o.dayStart });
+
+  if (moment(o.now).hour() < o.dayStart) {
+    dayStart.subtract({ days: 1 });
+  }
+  return dayStart;
+}
+
diff --git a/common/script/index.js b/common/script/index.js
index 7d012165f4..350f8c4c5f 100644
--- a/common/script/index.js
+++ b/common/script/index.js
@@ -1,6 +1,7 @@
 import {
   DAY_MAPPING,     // temporary, pending further refactoring
   sanitizeOptions, // temporary, pending further refactoring
+  startOfDay,      // temporary, pending further refactoring
 } from '../../common/script/cron';
 
 var $w, _, api, content, i18n, moment, preenHistory, sortOrder,
@@ -73,23 +74,6 @@ api.planGemLimits = {
   ------------------------------------------------------
  */
 
-api.startOfDay = function(options) {
-  var dayStart, o;
-  if (options == null) {
-    options = {};
-  }
-  o = sanitizeOptions(options);
-  dayStart = moment(o.now).startOf('day').add({
-    hours: o.dayStart
-  });
-  if (moment(o.now).hour() < o.dayStart) {
-    dayStart.subtract({
-      days: 1
-    });
-  }
-  return dayStart;
-};
-
 /*
   Absolute diff from "yesterday" till now
  */
@@ -100,9 +84,9 @@ api.daysSince = function(yesterday, options) {
     options = {};
   }
   o = sanitizeOptions(options);
-  return api.startOfDay(_.defaults({
+  return startOfDay(_.defaults({
     now: o.now
-  }, o)).diff(api.startOfDay(_.defaults({
+  }, o)).diff(startOfDay(_.defaults({
     now: yesterday
   }, o)), 'days');
 };
@@ -121,7 +105,7 @@ api.shouldDo = function(day, dailyTask, options) {
     return false;
   }
   o = sanitizeOptions(options);
-  startOfDayWithCDSTime = api.startOfDay(_.defaults({
+  startOfDayWithCDSTime = startOfDay(_.defaults({
     now: day
   }, o));
   taskStartDate = moment(dailyTask.startDate).zone(o.timezoneOffset);
diff --git a/test/common/algos.mocha.js b/test/common/algos.mocha.js
index a57a049233..293018c74c 100644
--- a/test/common/algos.mocha.js
+++ b/test/common/algos.mocha.js
@@ -2,6 +2,7 @@
 import {
   DAY_MAPPING,
   startOfWeek,
+  startOfDay,
 } from '../../common/script/cron';
 
 let expect = require('expect.js');
@@ -1190,7 +1191,7 @@ describe('Cron', () => {
     let fstr = 'YYYY-MM-DD HH: mm: ss';
 
     it('startOfDay before dayStart', () => {
-      let start = shared.startOfDay({
+      let start = startOfDay({
         now: moment('2014-10-09 02: 30: 00'),
         dayStart,
       });
@@ -1198,7 +1199,7 @@ describe('Cron', () => {
       expect(start.format(fstr)).to.eql('2014-10-08 04: 00: 00');
     });
     it('startOfDay after dayStart', () => {
-      let start = shared.startOfDay({
+      let start = startOfDay({
         now: moment('2014-10-09 05: 30: 00'),
         dayStart,
       });
@@ -1501,17 +1502,17 @@ describe('Helper', () => {
     let today = '2013-01-01 00: 00: 00';
     let zone = moment(today).zone();
 
-    expect(shared.startOfDay({
+    expect(startOfDay({
       now: new Date(2013, 0, 1, 0),
     }, {
       timezoneOffset: zone,
     }).format(fstr)).to.eql(today);
-    expect(shared.startOfDay({
+    expect(startOfDay({
       now: new Date(2013, 0, 1, 5),
     }, {
       timezoneOffset: zone,
     }).format(fstr)).to.eql(today);
-    expect(shared.startOfDay({
+    expect(startOfDay({
       now: new Date(2013, 0, 1, 23, 59, 59),
       timezoneOffset: zone,
     }).format(fstr)).to.eql(today);