Capital Gains

capital gains on purchase by company of its own shares or other specified securities section 46A

the word share purchase (buyback) is ONLY FOR THE EQUITY SHARES (for preference it is redemption which is not covered under section 46A)
other specified securities includes (u/s 68 of CA, 2013) employees stock options plan or other securities notified by the central government. currently, the central government has not issued notification in this regard

so, preference shares and debentures are not covered under this section

Oh okay. Thank you very much😊