Huh? Entered Time Machine folder shows items newer than my chosen timeline date?

– I open a folder in the Finder. – I do Enter Time Machine from the Time Machine menu in the menu bar. – I use the timeline on the right to find & click the date I want. – The stack of folder windows animates, presumably indicating that it's taking me to my chosen date. But the list shows some files whose date is more recent. I thought I'm supposed to be looking at a snapshot, so all the dates should be only the snapshot date or older. But the presence of newer dates makes me think something is wrong! Another separate question: Once I Enter Time Machine and pick a date in the timeline, can I navigate to other folders from the window and still be in the same snapshot date, or am I stuck in the window, and have to back-out and start from scratch again to get to a different folder at the same snapshot timeline?