Ok, I found this:
viewtopic.php?f=2&t=63106I completely forgot about this, so it seems you can change the timecode behavior
EDIT:
In the latest manual it is described on page 70 - Status LCD Controls
TimecodePress the ‘timecode’ button to toggle the main timecode display’s format between clip
duration and timecode. By default the timecode will be free running time of day code as
this is the most frequently used. If you press and hold the ‘timecode’ button for five
seconds it will switch the camera into record run timecode and the timecode generator
will flash as well as the first two digits of the large timecode display. This indicates that
you are now editing your preset timecode and allows you to set a specific timecode
number for your preset timecode.
Pressing ‘reset’ at this stage will zero the timecode and then you can turn and press
the menu wheel to set the desired value starting with hours, minutes, seconds and then
frames. When you are happy with the timecode, press and hold the ‘timecode’ button
again for three seconds to set this as your preset timecode point. You will notice that
the timecode generator now shows this value and will only increment when the camera
is recording giving you continuous ascending timecode values. To switch your
timecode back to free running time of day code, press the ‘timecode’ and ‘hold’ buttons
simultaneously for three seconds.
https://documents.blackmagicdesign.com/UserManuals/BlackmagicURSAMiniManual.pdf