Iirc, veritasium video said it was the weather report at the beginning of the message that fueled quicker decryption. So, not following same letter format each time might have helped.
Three so-called “cribs” are typically mentioned in literature:
1. Weather reports that were encrypted with Enigma for the High Command and then sent again encrypted with a much weaker cipher for (if I recall correctly) merchant fleet.
2. “Keine besondere Nachrichten” or “Keine besondere Ereignesse” - depending on sources. It means “no important news” or “no important events”.
3. “Heil Hitler” at the end of the message. This one is maybe an anecdote. If something like that would be sent I suspect the radio operators would send “HH” at most.
1. Weather reports that were encrypted with Enigma for the High Command and then sent again encrypted with a much weaker cipher for (if I recall correctly) merchant fleet.
2. “Keine besondere Nachrichten” or “Keine besondere Ereignesse” - depending on sources. It means “no important news” or “no important events”.
3. “Heil Hitler” at the end of the message. This one is maybe an anecdote. If something like that would be sent I suspect the radio operators would send “HH” at most.