Slow responding automation for "PreGain"?

Hi, I’m using Cubase 10 (Windows). I’m using volume automation for many years, but for that reason or another, I never used automation on the “PreGain”. Today I decided it makes more sense to do “pre-gain” riding on a bass track (rather than volume-riding). The automation of the preGain seems to “lag” - e.g., I reduced the pre-gain good 0.1-0.2 seconds before the next bass transient, but the gain was reduced slightly after the bass transient actually happened. Doing the regular volume automation on the very same case worked fine without any lagging. Is this a by-design behavior? Is this a bug?

(note that the bass track is an audio track, not an instrument track or a group track etc. - not sure if it matters, but just in case…)

Thanks! Erez