In past strikes this has been the case.
In the event your flight was cancelled, you could book into the same booking class if available or lowest booking class available in the same cabin in the event you still wanted to travel. They tended to review situations fairly regularly and updated rebook policies accordingly covering periods of the affected strikes and periods in which you could rebook etc... Also flexibility on alternative destinations and things like that. I'm fairly confident it would be the same if/when the next strike happens.

You certainly can't say BA aren't well versed or prepared - they have a lot of knowledge and practice in this situation!