Limit the burst speed controlled by limit_rate_after

Hello

I search since days how to limit the actual burst speed as well, not
just after the initial data is sent.

I wan that 4MB to be sent at 500KBps then the rest of the file to be
sent at 90KBps.

Is there any way to do this, or can someone write a patch?
I am ready to donate for the cause… :slight_smile:

Thank you.