Question on Drawmer dl241 limiter

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Nov 30, 2017
I have a Drawmer dl241 and i was wondering how the limiter section works. Could you help me analizing it? (I'm a beginner...)

I read this on the user manual:
"This limiter is very fast acting enabling it to
control any peaks without audible distortion. If the output signal is
so high as to cause the limiter to operate for more than 20mS, the
system gain is automatically reduced to bring the signal back within
range. The system gain is then returned to normal over a period of
approximately one second. "

But then again, on the company webpage it says:

"Peak Level. 'Zero Response Time', 'Zero Overshoot' circuitry : This provides an absolute limit to the peak level of the output signal, adjustable from OdB to +16dB above system level. When set to the required level, any excessive peaks will be stopped and the gain momentarily decreased if necessary. The 'Zero Response Time' is essential to avoid unpleasant distortion when mastering for CD or sending any signal to digital equipment. 'Zero Response Time' means that the DL241 provides complete protection from even the fastest and shortest signal 'spikes' (overloads), making the unit also ideally suited for speaker system protection in sound reinforcement applications."

Here is the schematics:

I'm wondering if maybe the limiter is actually 20uS or it's really 20mS. That's rather slow, given that the compressor section is supposed to go down to 0.5mS!

If I see correctly, the compressor section generates a CV which tunes the VCA output level. The Limiter is a separate section following the VCA, the peak circuit receives the audio from the VCA output and the audio flows out via the "Limout" into the output stage. The peak section generates a lim_cv which controls the VCA level together with the expander, and the compressor.

Is the minimum attack speed a limitation of the VCA chip? Or is it completely dependent on the peak limiter/detection section?
I would have thought there was some sort of clipping for transients which are not caught by the limiter?