LTE_WAKE seems to be a hardware provision for pycom processor wakeup from some event in the lte modem but I've never seen it implemented.

My mistake. It looks like PSM and eDRX are implemented. See here. You guys may well have figured that out already as the update was a little while ago now. That would seem to fix your problem @kjm. I haven't seen anyone with current measurements on it so I would be curious to see what you get.