What I find difficult to understand is airlines don't seem to be cancelling their orders with Boeing. This may be due to Boeing having very tight contracts but when the likes of RyanAir say they have problems and may lay off staff because they can't get the aircraft I would have thought they would be trying to source elsewhere.
Now I appreciate that the likes of Airbus can't just pull up replacement aircraft off the parking lot but with such doubt as to whether the Max will ever fly again then new suppliers would be my thoughts and I would be letting Boeing know that, along with court cases for loss of business.
If a company has always flown Boeing moving to Airbus requires an enormous investment in aircraft, spares, training and infrastructure. It's not something you can do in a few weeks.