How long can homogenates remain on the QIAsymphony SP without risk of RNA degradation?
FAQ ID -1941

Strongly denaturing conditions in the lysis buffer (Buffer RLT Plus) of the QIAsymphony RNA Kit keep RNases in an inactive state. Keeping homogenates on the QIAsymphony instrument at room temperature (20-25°C) for over 6 hours does not impair RNA integrity.