Okay so my elevation data has returned, but its wrong I am at 59 Meters my watch thinks its at 256 Meters. This I now think is to do with how the watch calibrates the barometric pressure on the watch. The pressure here over the last few days dropped to around 850mb very stormy wet weather. Its now started to increase and is now at 996mb. I suspect the correct reading will return when the barometric pressure hits around 1013mb. If this is the case apple needs to look at how the calibration of the barometric sensor is updated. (The good news is this does not look like a hardware problem) If you request your elevation through Siri it will give you a accurate reading.
fingers crossed that 7.02 fixes this issue
Would be nice if apple engineers glance over this stuff occasionally (JAWS READ THIS)