@mortommy Hi ! I decided to go with 2.1.1 on new sensors but still have the old 1.5.4 gw running. Had to change frequency to #define MY_RF24_CHANNEL 125 as the 2.1.1 sensors also registered partialy ( temp not humidity ) on the old 1.5 gw.
Also tried out #define MY_REPEATER_FEATURE Disabled this seems to do the opposite what i thought. Radio is never turned off ie. 17mA drain.
Added the following to try the lower the init etc. and it improves a little.
#define MY_REGISTRATION_FEATURE Disabled
#define MY_REGISTRATION_RETRIES 1
I think its a serious flaw that if the gw for any case locks up our sensors will drain the battery until it's back online again.