Rebooking onto a BA flight that's likely to be cancelled isn't a necessarily bad thing to do. Firstly it gets you a seat to TLV if the service runs (otherwise I'd just say do nothing at all right now). And then it kicks the re-routing down the road to a time when there is more certainty about what will happen. The situation is very fluid.

I'm just weighing up a trip end of October to Amman; one of the flights has been retimed but I'm not in any hurry at all to deal with that or cancel it.