Range by hour question

[cAstraea]

I'm trying to create 1 hour ranges and hit this snag where the times minutes might be different
for example trying to do something like
_.concat(Array.from(rangeDay1.by('hour', { excludeStart:false, excludeEnd: false })).map(m => m.set({m:00}).format('HH:mm'))));

because might have start time 15:10 and end time 17:00
I would expect to get -> 15: 00 , 16:00 , 17:00
however only 15:00 and 16:00 are returned

If i replace 15:10 by 15:00 all are returned