Go, IndiGo and SpiceJet moving ops temporarily to Delhi (DEL) Terminal 2
 

My mother is flying Spice Jet on April 2 and a banner on its site states that some flights will be moved to Delhi's Terminal 2 (not to be confused with the larger Terminal 3) from March 25. Upon checking further it looks like T1 is under repairs, and in the meanwhile GoAir (moved operations fully, according to the Economic Times), IndiGo and SpiceJet (partial operations) will use Terminal 2.

So if you're traveling these airlines from DEL in the next few months, please confirm where your flight is departing from.

Terminal 2 was the original Indira Gandhi International Terminal built in the mid-80s, and has apparently been renovated to take some load off Terminal 1.

Here's the Economic Times piece.

i believe the plan is to shift all goair, indigo & spicejet operations to t2....it would have happened a while back but all these airline were opposing this move in court till recently....

That about covers the LCCs or are we missing any? Which means T1 will be used for a different purpose?

They are expanding T1 also T1 was operating at over capacity. So they needed to move some of the flight operations out till they can finish the expansion work. All 3 carriers operating out of T1 resisted the shift. It would have made much more sense if for instance only Indigo moved all it's operations to T2 - but they acted like major tools about moving.

Now this is going to create a lot of confusion for customers for sure. Despite all the efforts that the airport authorities and the airlines put in to make customers aware of their terminals etc. Indigo & Spicejet are now operating from all 3 terminals. A few people are going to miss their flights.