I've seen CKK, a company I hold, use this 'convertible notes' method of financing over the last year or two.
One problem is that con note holders can manipulate the share price down through on-market selling of small parcels (by proxy), strangling the share price over time in order to convert larger parcels (of con notes) at the cheapest possible rate.
This may be harder to do with AEB because the market cap is larger, but with CKK having a market cap of only 13m, bots would use 5-10k sell orders to achieve the manipulation.
CKK has 2 mill worth of con. notes (40 notes at 50k each) sitting on the books, with a 9.5% interest rate applicable, expiring in February coming and CKK holders can't wait to see the back of them.
AEB Price at posting:
50.0¢ Sentiment: None Disclosure: Not Held