Well to cut the story short I have been always baffled of the Jagdpanzer IV armor value of 14 which is same as Panthers. But previously I thought that Jagdpanzer IV had "only" 60mm of frontal armor until it was upgraded in Autumn 1944 so armor value of 14 always seemed to me bit off. 
Well I finally found out that the Jagdpanzer IV frontal armor was boosted from 60mm to 80mm at some point in March-April 1944 (after some 120-150 were produced) and not when Jagdpanzer IV switched from L/48 gun to L/70 as I did previously though. So by Normandy battles the uparmored Jagdpanzer IV would had been the only type as Jagdpanzer IV that were in Normandy would had come straight from the factory pretty much. Any Jagdpanzer IV with the lower armor would had been already being deployed to Eastern Front.
Funny what you find out when you get bothered by something.
Well I finally found out that the Jagdpanzer IV frontal armor was boosted from 60mm to 80mm at some point in March-April 1944 (after some 120-150 were produced) and not when Jagdpanzer IV switched from L/48 gun to L/70 as I did previously though. So by Normandy battles the uparmored Jagdpanzer IV would had been the only type as Jagdpanzer IV that were in Normandy would had come straight from the factory pretty much. Any Jagdpanzer IV with the lower armor would had been already being deployed to Eastern Front.
Funny what you find out when you get bothered by something.