title: Can I change the Azure Function Event Hub trigger starting checkpoint?
body: <p>When I stand up a new Azure Function listening to our event hub, with a new consumer group, it gets all the messages that have ever been sent to the event hub, even from months ago somehow. I thought setting the message retention on the hub to one day would limit that, but apparently not. Anyway, I really only want the new Azure Function to receive events from the initial deployment or testing point onward, however I don't know how I can specify that initial starting checkpoint, since that stuff is magically done in storage by AF.</p>
  
  <p>If I'm doing the hub logic manually I can specify this checkpoint and start from an arbitrary time, such as the current time. Is there a way to replicate this with an Azure Function?</p>