I noticed this for the first time the other day, although it must have been happening for ages. I tried importing a dataset that is an extract from our database, but I ran into an issue (one row of corrupt data threw the whole thing off). I had selected "Replace File if it already exists" and realised that when the import process starts, it deletes the already existing dataset before checking the new data set. This seems backwards to me - shouldn't the new file be checked and verified first, then if everything is Ok, delete the previous SAS dataset? I wanted to see if the corrupt row had been previously imported or if the issue was a new one, and I couldn't do that.
I will now be keeping archived copies of my extracts so I can go back in and check, and will also be renaming my previous SAS dataset to a new name before replacing.
(Tagged with Importing and Data Management as it doesn't really fall under the other tags....)