Self destruct timer for pictures start when download starts, instead of once it's been downloaded

Using telegram 1.1.0.92

Set the self destruct timer for 3 seconds, and while receiving a big file, it dissapeared even before finishing download.
Tried with a smaller file, and I managed to download it in 2 seconds and see the picture for 1 extra second, but this may make secret chats less useful (if the message doesn't even arrive to the recipient).