There is a setting that controls whether it will automatically try and send the form back: go to Maintain Templates, click on the template and then on the “Template: xxx” line at the top.  In the first tab there is a tick box to “Automatically send back finished reports”.  Ticking this box will send reports back automatically rather than waiting for the Send Reports function in the opening menu.

If there is no connection available when such a form is released from the device then it will try again a few minutes later. Further failures will cause further re-tries with diminishing frequency meaning that a form should come back “by itself” eventually.  

Using the Send Reports option can be useful to force through any reports that are awaiting a re-try, or any reports which are not set to go back automatically and I would recommend that users do this at the end of the day, just to ensure that there’s nothing outstanding.