Key expiration question

[listo factor]

On 06/13/2017 01:02 PM, Peter Lebbing wrote:
> 
> An expired key will definitely not be able to issue valid signatures
> after the expiration date. 

There is nothing ~in the key itself~ that prevents any key
from being used to create signatures, it is only a feature of
the software used to create the signature to compare a date in
the key with some arbitrary external information (computer
system date) that may or may not observe such limitation.
The key expiration date should therefore be considered a only
~suggestion~, and not a ~limitation~ for creating or not
creating signatures.