https://www.newscientist.com/article/2146739-slingshot-around-titan-is-the-beginning-of-the-end-for-cassini/

The probe’s last Titan flyby on 21 April bent Cassini’s orbit to enable it to fly between Saturn and the planet’s rings. Today’s final slingshot past that moon will speed up the spacecraft and set it on an irreversible collision course with Saturn in five days’ time.

“With that final kiss goodbye from Titan, we are going so deep into Saturn’s atmosphere that the spacecraft is not going to have any chance to come back out,” says Earl Maize, Cassini project manager at NASA.