They will always be on the site, on the rosters of the teams they played on that will be on the "rosters" pull-down menu. You don't just delete someone from the roster of the teams they played on when they graduate or transfer.
UR, like many schools, uses Sidearm for their athletic web pages. Developed by guys at Syracuse, it started becoming the go-to web page system in 2015-16 or so and is a fairly easy system to navigate. I expect the roster will be updated shortly.
Speaking from experience in working with this system, the biggest things that must be done before the roster can be updated is, new photos for every player must be taken, and everyone's bio must be updated with highlights from the previous season, which can be rather extensive work, depending on the sport.