Originally Posted by waffle

No, you won't get any EU261 compensation for a strike (and one that's definitely outside the BA's control), but you will get a free rebooking or a full refund – they can't take your money or Avios and not let you travel.

Of course, if you only want to see ITB (not that Berlin isn't a worthwhile destination in its own right), it'll have to be this weekend, so you'd need a plan B. The closest nonstop BA destinations are Hamburg (HAM) and Hanover (HAJ), both about 2:15 hours and €60–80 from Berlin by train.