I recently added a couple more cameras to my Blue Iris install and now I am losing history of alerts. The clips are still there but the indicator in the BI interface is gone and the web interface doesn't show them.

I noticed this yesterday, I had 24 hours of alerts and today I check I only have 12 hours of alerts. I have 7 days of clips though on all cameras.

Any ideas what is going on?

I am running version 4.8.6.3

I actually figured it out yesterday.

Turns out I had enabled "store alerts as hi res files" enabled on one camera. When I added my new cameras I copied them from the one camera that had that option enabled. So the 1GB limit in the Alerts managed folder was being hit and alerts were getting deleted.

Interesting it was deleting all alerts and not just the hi res ones... but I fixed it by disabling that hi res file option on all cameras.