You can convert the options anytime between now and expiry....

You can convert the options anytime between now and expiry.
Correct, also take into account your initial purchase price for options.

The main beauty of options is leverage, if the heads reach 20c, your oppies will be worth (at 2c strike) hypothetically, 18c. Assume you purchase at 3c per option

Initial cost = 500k x $0.03 = $15,000
At 18c = 500k x $0.18 = $90,000 (600% of original outlay)

However, if you went for the BRV shares at purchase price of 5c per share

Initial cost = 500k x $0.05 = $25,000
At 20c = 500k x $0.20 = $100,000 (400% of original outlay)

All IMO, not financial advice.