I am currently deployed over Iraq as 21B. My reservist Unit has change MTOW. I've been a 21B for two years out of six-two on my contract.
I want to reclass to 25B (which I understand is a critical MOS as well) because thats my profession on my civilian job. No only that but looking foward to become a WO 250A. Does anybody can point me in the right direction?

Is your reserve unit changing or would this be a voluntry change?

Also, it's MTOE ... not MTOW.

Army units are divided between Table of Organization and Equipment (TOE) units that are doctrinally defined operational Army field units, and Table of Distribution and Allowances (TDA) non-tactical, non-doctrinal units such as fixed facilities, command and control headquarters, and other Army/Joint organizations, both in Continental United States and overseas. At least since 1996, the Army has sought, where possible, to convert TDA units to TOE status. Units defined by a TOE typically have alpahnumeric designators, while TDA units do not.

My reserve unit is changing... 21B was one of the few jobs available to me because I was not a citizen at that time. So I thought, I join, become a citizen, and then change my MOS... It seems pieces a falling in the right place for me to change easily from 21B to 25B

I understand your unit is changing ... from what to what? 21B to 25Bs or something else to 21Bs?

I dont have that quiet clear but among us they are saying that they are going to leave to a different units because they dont want to be doing construction, I dont know if it is horizontal or vertical. Its quite hard for me since I am part of the 841 EN BN but attached to the 478 EN BN during this deployment. Anyways, they are not changing to 25B thats for sure. Regardless, is it posible to change from 21B to 25B? I understand that combat engineers are one of the most needed MOS in the army.

There will be a resident expert in reserve affairs alng shortly.