Bed and Breakfast revolves around the blaster synergy that does immense damage even at only 2 blasters. 4 Blasters will be strong midgame, but late game you should look to add in Rebel with Ziggs to compliment Gangplank. At level 9, you can add in ASol which will also help the team a lot.
If you find lots of bows and swords, you can look to build items for your blaster carries. If you start the game with a lot of brawler units, you can seamlessly transition into a blaster carry comp.
Level up on 2 if you are strong and want to start a win streak.
Level up to 5 after the carousel on Round 4 if you want to continue your win streak.
If you were lose streaking up to Round 7, you can level up to 5 if you don't think you can beat the creeps.
Level up to 6 if you are on a win streak during Round 2 or level up to 5 if you haven't yet.
Win streak or lose streak, you should normally catch up to level 6 on Round 2. Roll a small amount if you are very weak and need to stabilize.
Before the fight on Round 1, level up to 7 and roll down if necessary.
7 After raptors, level to 8 if you haven't already and roll down to complete your team.
If you put a Zephyr on your Blizcrank, you will be able to hook the 2nd furthest unit.
Also make sure to place your Blitzcrank close to Jinx so that she will target said unit and proc her passive ability quickly.
4 Blasters will be good for transitioning, but in the late game, you want to ideally find powerful late game units over running 4 blasters.