I've enabled Push for both of my Yahoo mail accounts for quite a while now (a year maybe) on both my iPhone 4 and iPad 2 and until about 2-3 weeks ago, never had any problems. I haven't changed any of my account settings or changed any of the mail settings on either device but now I only get my email if I open the app. I temporarily switched to Fetch every 15 minutes and was once again getting email messages without having to manually open the app but prefer the immediacy of Push. Also, the fetch schedule is supposed to be used when Push doesn't work yet that doesn't seem to be the case either. If I go into the Advanced settings and set the Yahoo accounts for either Push or Fetch, I never automatically get email if the Push setting is set to On. Anyone with similar experiences and if so, were you able to resolve it?