Hey Sebi,
first of all: thanks for the module you shared!!
I implemented it on my site and it worked well but I now face the problem that each day again the select area where you choose which templates should get the releasetime fields deselects itself?!? So the pages that should get deactivated show up each morning again … That happens either over night or when I get logged out of my admin area automatically after a while (couldn’t find that out yet). Have you had this problem before as well?