@Jan Turecek Apologies for the delay in response and all the inconvenience caused because of the issue.
I had discussion internally and got to know that Azure Security Center JIT currently cannot be enabled for scale set VMs, only individual VMs. This is not a supported scenario yet but this feedback is already into pipeline and there might be updates on same by next semester. Currently we do not have an ETA on this but rest assured it is being worked upon.
Hope it helps!!!
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