iOS 8.1 Does Not Download All iCloud Mail/ Keeps Cache?

Hello,

I have setup and enabled an iCloud e-mail account on all of my devices and was successfully able to use the Mail app in Mac OS X Yosemite to copy mail from my Yahoo! inbox to my iCloud inbox. All e-mail copied from Yahoo! Mail appears in the OS X Yosemite Mail app as well as in the iCloud.com site, however, my iPad Air 2 and iPhone 5 both running iOS 8.1 does not download all of the mail from iCloud. I have tried the following on both iOS 8.1 devices with no success.

- Disable iCloud mail and re-enable

- Sign completely out of iCloud and sign in again, then reconfigure all iCloud services including mail

The result of both steps is that the incomplete list of e-mail in the iCloud inbox just reappears in the Mail app instead of downloading from iCloud again. It looks like the incomplete list of e-mail is stored on the iOS device and signing out of or disabling iCloud mail just hides it; re-enabling or signing in merely shows it again. This appears to work differently than my Yahoo! Mail configuration where if I sign out of or delete the Yahoo! account and reconfigure, iOS downloads a fresh copy of all e-mail in the inbox and all other folders. Here are my two questions:

- How do I get my iPhone and iPad Air 2 to download ALL e-mail from my iCloud mail account?

- Are my suspicions true? Does iOS actually store a cached copy of iCloud mail on the device when the service is disabled and just "redisplays" it when re-enabled?

Thanks!