When you see different classes of shares like this, it is usually different voting rights. Often they will structure it so one set of shares has more voting power than the other, and management will primarily hold the class of shares that has more voting power. Gives them a bit more flexibility in terms of decisions.
In this instance, BBD.A has 10 votes per share while BBD.B has 1.
You'd think it would be a no brainer to buy the shares with more voting power but the problem is there is liquidity issues as they are rarely traded. Retail investors would be buying BBD.B. Canadian Tire has a similar structure.
The company has gone on quite a run here since it landed the deal for 50~ jets. After years of struggles profitability wise it seems to be turning the corner a little bit. The company is a tad pricey for me here, plus it is not a business I typically like to buy as margins are typically pretty thin. But if its strong results continue here over the next while I wouldn't be surprised if we see higher prices. Just not something I'd want to hold long-term.