>>49
https://spaceflight101.com/long-march-5-shijian-18/chinese-long-march-5-fails-on-second-mission/
によると
The two YF-77 engines of the core stage were expected to fire until 465 seconds
into the flight (7 minutes and 45 seconds) to be followed within three seconds
by the separation of the stages and the ignition of the two YF-75D expander cycle
engines on the second stage. However, stage separation did not occur until 570
seconds into the mission, 105 seconds later than specified.

１段目の燃焼は465秒（7分45秒）で、１段目切り離しと２段目点火はそれから3秒以内の想定だったが、570秒の時点で切り離しは行われず、105秒の遅れ

The second stage fired up at T+575.3 seconds according to telemetry displays at
mission control, aiming to place the stack into a Low Earth Parking Orbit.

T+575.3秒で二段目に点火

となってるので不具合ゆえに二段目点火が575.3秒になったのであって、元から575.3秒だったようには読めないのですが