The dat file was last updated when we found our last prime. 90% sieve point was at 162T at that time (http://www.aooq73.dsl.pipex.com/history/scores_p_2003_12_20.htm). I think it's a bit early to update the file.
On the other hand, I guess they're talking about the results.txt file. This is important only if you are regularly downloading that file for factoring reasons. The purpose, I guess, is to lower the bandwith needed for the process. The current size of the file (zipped) is 1.56 MB.
I dunno about up to 300T, but I think we can safely increase the lower limit of results.txt file up to 132T* (or even 100T is just fine). Roughly 45% of the factors in the results.txt file are 25T<p<100T. And there is an additional 10% between 100T and 132T.
* 132T is the 100% sieve point as of the last dat file.
If we want to increase the lower limit to 300T, it's also fine. We'll get rid of the 80% of the results.txt file size. On the other hand, we'll have to update the dat file to avoid some unnecessary P-1 tests being performed. (The impact would be less than 1%. Still each unnecessary test is a waste of computer time anyway).