Doubts regarding Infy share buyback

I have a question regarding Infosys buyback or I would say more related to buyback of shares
Suppose I have 50 shares of Infosys and out of that 15 shares are eligible for buyback. I have already received the communication that 15 shares are eligible for buyback.
I guess the buyback will apply in FIFO way, so the first 15 shares I bought will be eligible for buyback.
Now, before the buyback process, I sell 15 shares of Infosys.
Now I have (50-15) = 35 shares available.

So,
1.How many shares will be available for buyback now? If it around 15% of total shares, then I guess around 10?
2.Will the buyback follow the same process of FIFO?

A post was merged into an existing topic: How do I participate in the Infosys Buyback offer?