Worst case just pick up a 25k/year office job to keep you ticking over.
Spending three years not earning and going to university to get into 50k of debt just to have a ‘backup’ seems pretty silly. Chances are in a downturn you’ll need a backup for two/three years if that and unless you’re making 100k plus you’re far better off having just done the flight training in the first place and picking up a generic job if you need to.
And in any seniority airline the three years you spent getting a computing degree could well be the reason you’ve been made redundant and not kept the job in the first place.
If you want to spend three years boozing and chasing the opposite sex then yes uni is awesome but don’t put yourself through three years of something you don’t want to do just to have this mythical ‘backup’. How many companies are actually hiring and offering top pay in downturns? Not many...