Notification email is sometimes delayed

Hello,

We are a week into using Gravity Forms for processing day pass sales for a small nature preserve. So far 99% has been great! Thanks for the excellent product.

Two out of nearly 100 transactions, however, have had their notification email delayed by several days. The paypal receipt comes through just fine, but not the notification from Gravity Forms. This is problematic, because we want people to print this email as their day pass.

Any thoughts as to what could occasionally cause the email to delay? Again, it works fine for almost everybody, but we do have two verified incidents where the email was sent days after the transaction.

Thanks!!!

Ah yes! That's it! They were people who paid by echecks, and the emails are not going out until the check clears. Now to think about how we will handle this...