Restudying a site makes sense for several reasons. For one thing new scientific tests are developed over the decades, also digging deeper can find new things. Now that the dogma of nothing before Clovis is being seriously challenged, new deeper digs are finding that indeed there was SOMETHING before Clovis in several likely locations. New knowledge of major world events means that you can start looking for information that did not occur to you originally. For example now that the Toba eruption and the Dryas event are being looked at there are a number of new ideas about what mankind was doing 73 thousand years ago and 12 to 13 thousand years ago, not to mention where he might have been doing it.
I understand, and am a firm believer in digging deeper to find even older stuff. But in some of these theories one must also dig deeper into who is funding and promoting the study and theory. In this case Durham University. Because of the source there is a very strong indication that this study could be biased towards supporting Anglican theology with science.