Take a magnifying glass and look closely at the stem section connecting the
pod to the spike. A plant will cut off water/nutrients to the pod by
twisting this section of stem and strangling the pod... which dries out and
then cracks open.
There are three lines running parallel along this section of stem. If they
are still running nice and straight then your pod is still
growing/developing. If the plant has already started twisting this small
section of stem and completed at least a 120 degree "twist" then I would
feel confident in processing it.
And of course , if your pod has starting turning yellow then it is time to
HBI, Producers of Fine Orchids in Flask