Apparently in Moodle 2.2.2 you can sort issued certificates report by date, but it is not available in Moodle 3.0.4. Is there an alternative way of doing that?
Some PHP needs to be altered within the plugin, I hope that I'll find some time to look into this. Few years ago, I've altered this plugin's script to export sortable excel file unlike the one I get from that offered "Download in Excel format" button...