In reply to Stuart Johnston:
good luck.
northern myanmar is not controlled by the junta, instead loosely held in a state of cease-fire with several tribes that make the govt look like babysitters (wagh, shan etc).
getting to the peaks is really difficult as visas only permit you entry to central myanmar. beyond that you need escorts and liason officers and even then cant get too close to borders, especially anything towards india.
even from the chinese side its heavily patrolled. theres one crossing at ruili that occasional one-way (from china) crossings can go thru, but its non-stop with escorts all the way to central myanmar where the normal visa comes into effect.
all that said, ive heard of one group getting up to some peaks in the far eastern himalaya (lead by a guy who does seven summit trips as well). took a year or two of redtape.
as for the monsoon - it sure does reach the mountains here. the eastern himalaya has some of the highest rainfall on earth. SE tibet, W yunnan, sikkim, arunachal etc all get hammered. sub-tropical rain forest goes all the way to 4500m.
its a shit of a thing. the eastern himalaya has so much potential yet the bloody governments of the world constantly get in the way.