IN866 frequency

[virtualroughneck]

I am neither a coder nor an IOT expert but have fair experience in working with boards in the US915 region
My team is experimenting with Adafruit feather board M0 and they are using the helium network, I guess the frequency in866 works?
I just modified the following code
//Make sure that we have exactly one target region defined.
#if CFG_LMIC_REGION_MASK == 0

define CFG_eu868 1

to
//Make sure that we have exactly one target region defined.
#if CFG_LMIC_REGION_MASK == 0

define CFG_in866 1

and ran the sketch, will this do the work or I still have to make some modifications elsewhere
(I saw no major errors)