Context Capture can't properly read height data from photo...need help


I need help with strange CC behaviour...can't track it down to the source of the problem. I have set of photographs done by drone with GPs positions in meta data.

See below:

CC reads it as WGS and this is what I'm getting:

same as above but converted to OSGB:

My GPS altitiude is set to Sea Level:

Now as you can see Z values are all out of the place...image was taken ca. 53m above ground, CC reads it as 0.6m, OSGB shows -53m and funny thing is that we have GCP which are like:


So GCP and image Z value are correct but CC seems to have hard times trying to interpret them. This makes GCP totally unusable cos after AT my model is like 30m below GCP and CC fails to match GCP locations with any of the after all I'm ending up with 3D model correctly sitting in X,Y but Z is a total abstraction. I checked the same photographs in two Cc versions and and results are the same...

Any idea what is wrong ??.