Yeah, same! I realized the same thing too after i updated to 6.3.3 and same goes to 6.3.4, the server will barely last 3 days and it will unexpectedly shutdown and restart with a parity check. Didn't have this issue before this and it can run up to two months without restarting.
Will be installing this and monitor the situation and will post my logs when it happens again. As of now there's nothing much in my logs as errors before the shutdown are not captured. Will wait for the next crash and update here!