Clarification on meaning of address_verify_positive_refresh_timer

[Damian]

Hello mailing list,

I would like to understand the address_verify_positive_refresh_timer 
parameter. The documentation states:

The time after which a successful address verification probe needs to 
be refreshed. The address verification status is not updated when the 
probe fails (optimistic caching).
It does not explain what happens with incoming mails that are checked 
via reject_unverified_recipient. Lets consider following events with 
default timer values:

An incoming mail for recipient X is encountered the first time, i.e. 
there is neither a positive nor a negative cache entry. A probe is sent 
out and the upstream SMTP accepts the probe. Postfix creates a positive 
cache entry for X with a validity of 31 days. The incoming mail is 
accepted and forwarded to the upstream SMTP.

Suppose there are no further mails for X for the next 8 days, but the 
upstream SMTP has invalidated address X on day 5. On day eight, a mail 
for X is again on its way. I understand, that a probe will be sent out, 
and because the upstream SMTP rejects the probe, it is considered 
failed. However, due to optimistic caching, the address verification 
status for X remains positive at least until day 31. But what happens 
with mails for X between day 8 and 31? Will they be accepted by Postfix 
and then bounced?

Thanks
 Damian