Data not logged due to incorrect date setting

I am using EmonBase to measure power. It has no connection to internet, so the date setting on it is wrong. I installed the system and let it collect data for a week. I can’t see the data or the plots. I was under the impression that no data was logged because of wrong date but then I realized that there is no way for this isolated system to know the actual date and time since it is always offline and so it must have logged that data. Why does it not show the plots and is it possible to obtain that data, if so how?
(When I correct the date and use it, I see the new data but I wish to see that old data which I collected during that one week period with wrong date.)