Potential $500K+ redundancy - WWYD

Hi all. My husband could potentially being made redundant.

His current salary is ~400K, working FIFO 2:2 in a specialist field. Should he be required to find another job it will likely be a significant drop in income. He’s 52, I’m 47.

We have:
Fully offset mortgage
~180K shares
~80K ETF
$160K cash
$600K his super, $160K my super (actively making back contributions)
No debts
2 young adult kids still at home, one teen.

In this uncertain financial climate, what would you do with the redundancy payment?