does this 28 days extension been happening specific to ur sim/ ur circle ?
previously used rs45 auto deduction and also used *127*777# for stopping auto deduction. but never tried Rs100 top-up.
Airtel havent mentioned, neither any other person have highlighted this?
I am planning to PORT one number to airtel prepaid.
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I am not aware if different telecom circles make a difference in this scenario.
For Airtel Prepaid, there are 2 circles in my state:
1) Tamil Nadu circle
2) Chennai circle
All of my numbers are of the Tamil Nadu circle.
I don't think there are much differences between the 2 circles these days. It used to matter during the earlier days, when Roaming Charges were a thing while travelling between circles.
There are no intra state roaming charges anymore.
The only visible changes that I notice when I go to my place in Chennai, are:
1) The letter 'R' gets displayed next to the mobile tower signals on my mobile, indicating that I am on a 'Roaming' network.
2) Mobile Data does not work unless I turn ON the 'Data Roaming' feature in my mobile.
To be honest, I had not tried the new Rs.100 top up (with reduced talk time) before this year, either. I guess most of us do not use top ups nowadays, ever since they stopped offering Full Talktime. When I tried it the first time this year, I did it because I was offered some good cashback on the Freecharge website. And I did not want it to go to waste. That is the reason why I even tried the 100 top up in the first place. And therefore I stumbled upon the 28 days validity extension, accidentally.
So to answer your question, I am not sure if the 100 top up would make a difference between my circle (Tamil Nadu) and your circle (Maharashtra, I'm assuming based on your profile).
May be Airtel is offering (secretly!?) this feature as a gesture during Covid-19 days. Because users from this forum have reported that the 48 data pack (3GB Data for 28 days) is also acting as a main pack, by offering 28 days validity (like what the 100 top up is doing).
May be these are (100 and 48) Covid gestures by Airtel, or may be this is a glitch in the Airtel systems. I am not aware of that. As far as I know, there have been no formal announcements regarding these from Airtel.
As for you, I would suggest you to have a friend or relative in your telecom circle who has Airtel Prepaid, do the 100 top up and test it out for you, especially if you are planning to port your number to Airtel just for this feature.