"Warning: Your database transaction log file size has crossed the threshold" since updating to build 11141

"Warning: Your database transaction log file size has crossed the threshold" since updating to build 11141

Since upgrading to build 11141 we have been receiving the following email on a daily basis. 



As you can see, the last log backup is recent and when checking the SQL DB, it shows that we have 93% free space. 



Our threshold settings are as follows:



Is this a bug or am I missing something obvious?


Thanks,

Richard