Dates & duplicate files - observations

[ElizabethD]

I'm just trying to get some rules about this site file section:

1. How does the date work on the screen where NEW flashes after an upload of a file? I re-uploaded a file day after initial upload. I see that the timestamp on this screen did not change even after refresh. Should it?

2. Within approximately two minutes, I uploaded one file twice. A 'file exists' or 'replace?' dialog didn't follow. Is this a problem or is it a feature in anticipation of likely multiple upgrades for the same equipment?