Why Micromax company does not provide firmware updates for Micromax Canvas Lite a92 (Dual-Core processor)? It's also a phone of Micromax Canvas Series like the others. The company cannot do this with A92 users.
The only way to obtain more information about this aspect is to contact the company. You have a contact form available on the website which you can use to ask questions related to their phones. Make sure to use real data and a valid email address and you will get the needed information.