Many like you face the same problem. In your case the increment (if the date of resumption falls between 1st January and 30th June of the same calendar year which is 19.01.2015 in your case) will resume on the date of annual increment i.e. 1st July. So, if you have passed the B.Ed. exam, your increment will resume on 01.07.2015. Now, as of the number of increments you are entitled to get there prevails a confusion. As far as I have come to know from the related documents (supported by the concerned authority of D.I. Office, Jalpaiguri) you will get two increments- one, be attentive as many do not understand it, the increment that you are entitled to get with effect from 19.01.2015, but you will actually get on 01.07.2015 (as per the directions on increments in ROPA-2009) on completion of B.ed. and two, the normal increment entitled to a serviceman annually. But the point is many other D.I. Offices have expressed confusion regarding this matter. So, I suggest you to consult a competent authority for further details.