@Ironborn if you are hoping to hear whales in the TCI, your best bet would be to go there in the spring (March). The whales are not "local" to the TCI, but in March the whales migrate through the area.
The Aggressor and Explorer liveboards don't operate in the T&Cs in March, they divert to the Silver Bank to offer whale watching and snorkeling cruises from about mid-Feb to early or mid April.