lucy24 - 5:55 am on Aug 2, 2013 (gmt 0)
in no particluar connection with each other, time-wise...
That's normal for a robot. It handles a redirect the same as a newly discovered link: the new URL goes on a shopping list for later. The old URL is logged as "This URL redirects to such-and-such".
It makes sense if you look at it from the other side. The new URL doesn't carry a built-in tag that says "This page was formerly known as such-and-such". So its existence doesn't really give any information about the status of the old URL. True, most robots do get the hint after receiving the identical redirect eighty-seven times in a row. But remember, this is the same bingbot that will check your robots.txt fifty times a day on the off chance that something might have changed :)