Strange that it is working for you @Elefant_Man now.
I am on version 5.8.8.12 and it is still not jumping back to the start of the alert when I double-click on an alert in the alert list.

I have 5 cameras and one is actually working as it should and it is an AXIS P5635-E Mk II PTZ.
My 4 other cameras that are not jumping to the start of the alert are AXIS P3364.
I have triple checked the settings for the 4 AXIS P3364 and they are identical as the AXIS P5635.

I have emailed Blue Iris support with my logs.