I think more flight crew CR in the immediate future is, on balance, unlikely. It has been clear for a very long time that winter this year was going to be murder for the aviation industry. As incompetent as I believe our managers sometimes are, even I can't believe they really thought they were going to reach breakeven cashflow in Q4. They must have known it was going to be a disastrous winter, and if their intention was to crew accordingly they would have needed to start the process earlier than now. Any new redundancies will require a 45 day consultation period, followed by a 3 month notice period (or pay in lieu) plus redundancy pay. Even if you started today, that almost gets you to spring 21. A costly exercise reaching its conclusion just as things may be starting to improve. Far more likely in the short term is further unpaid leave, which is a lever we know BA is willing to pull (unlike part time).
The real problem is summer 21. Today, Heathrow reduced their passenger forecast for next year from 62 million to 37 million (2019: 81 million). If that is even close to being accurate then further CR will be inevitable next year. There are some reasons for optimism however. First, scientific opinion seems to be that we will get a vaccine or vaccines by the end of Q1/21. We don't know how effective they will be but it's a fair bet they will make an appreciable difference to the trajectory of the epidemic. Additionally there are several promising trials of therapeutics nearing conclusion. Testing technology is rapidly advancing and pressure will only increase on the government to find a workable replacement to reduce or eliminate quarantine in time for summer next year. More broadly, I think we will see public opinion starting to shift soon, not just here but elsewhere, when the cost of all this (both societal and monetary) starts to become more obvious. The public have been mostly shielded from the worst effects of restrictions by bailouts which cannot continue for much longer.
In terms of it being existential if I'm wrong and things drag on and on, on a political level I have never personally believed that the government, and particularly this government, would be prepared to see British Airways completely disappear. In terms of optics, as a first step out on to the world stage as a newly "independent" and global free trading nation it would be a spectacular own goal. A national embarrassment. Not that they don't have form of course - pick your fiasco/u-turn of choice from the last 6 months - but when push came to shove would they really watch the national carrier sink? I find that hard to believe personally. That's not to say government intervention would be especially pleasant for staff or shareholders, but I suspect it would happen nevertheless. Let's all hope we don't get to find out if I'm right.