Preferential allotment vs equity warrants

Can anyone pls help me with the below queries - Thanks in advance: Query 1) Are the below the only key differences between Preferential issue and Issue of Equity-warrants to a Promoter of a Listed company: In warrant, owner has an option to convert or not - depending on market-price then. In warrant, Promoter has to infuse only arnd 25%. But then, this can be achieved by issuing partly-paid preference shares also, right? Query 2) Like we have 18 months Conversion period for Equity-Warrants, is there a specified 'Regulatory' time-period for conversion of preference shares to equity shares Query 3) Can we pledge an Equity-warrant for granting a loan (like shares are pledged for lending). How does this work - since on Warrants, only ~25% of the amount would have been paid?