Visited the Ministry of Hotels and Tourism office at Yangon a few days back and found out that there are still complexities in crossing over to India via the Tamu border post. We have Indian passports and had crossed into Myanmar from Thailand, and this makes us not eligible to apply for a permit to cross into India via Tamu. As other posters have noted here, the permit (to get to India via Tamu border post) is now given only if you enter Myanmar via India. We walked into a few of the travel agencies nearby, and was presented with similar answers.
Hope this helps in anyone planning to use the Tamu border, atleast in the immediate interim - your only option is now to fly out of Myanmar.