Sorry but I don't understand.

I have activated SMTP Blocking:

Inbound Weight Threshold 60

But I'm seeing that messages over 60 are still being delivered

Also I don't understand the pattern

I seem to have understood that:

The message is received in smtp server to server

Then the smtp session is closed. Only then is the message processed by the delivery queue and therefore all the antispam checks are carried out on the message

This means that I cannot reply with an smtp message like

421 4.7.1 Spam Detected - contact xxxx@xxxx.xx for more details

I understand that the blocking system simply deletes the message (which then as mentioned above does not seem to work). I have seen that there is the possibility to set a bounce message, but since it is spam it is madness. A smtp message would be much better. A true false positive would be handled by the originating server if needed.

However, I remain firmly convinced that it would be better to implement a function of

Over a certain weight of spam quarantine the message inbound spam

I would have an outbound quarantine and a separate inboud quarantine