Fallback to OptFlow on GPS loss?

Hi,
we have a OctaQuad equipped with GPS as well as optical flow. Currently we are fusing both.
Is there a way to enable automatic fallback to just optical flow if the GPS glitches or becomes unavailable in flight?
As far as I understand the EKF failsafe would be triggered (e.g. land)

Hello @WARGRaph try using lua scripting to detect GNSS issues and reconfigure parameters to ignore GNSS.
It should continue monitoring the signal quality so that it reactivates it once the conditions allow it to.