Does the extender store multiple records fro the same key

Hi, 

I'm using GP extender with the employee card to track additional info for employee

just realised that a user updated the extender additional info, when i deleted the updated record, saved and exit, then i open the same form i found that it brought back the previous info before the update.

Does extender keep the history for the previous records? is there a settings for that

Also I have a query that retrieve the employee info + extender info

I noticed that there is multiple records returned by the extender query

Thanks for any help