Is it legal for employers to terminate, reduce work hours or ask employees to take excess leave during this crisis?

Sharing this question on behalf of community member, Fiona Meyerman:

Hoping someone might be able to answer for me. I didn't want to tie up the line to fair work.
Partner works in an industry that supplies to pubs. The actual amount they supply to them is only a very small portion and hasn't had a massive impact. They were told yesterday by head office 3 full timers needed to be let go by next week. Their manager went to head office to fight for them as they haven't had a massive reduction in work load. Head office came back this morning and have said that either 3 full times employees loose their job or 4 full time employees have their working hours reduced to 28hrs per week and they have to absorb the other 10 hours from their annual leave. They have advised they will review this structure in 6-8 weeks and they may still loose theirs jobs. Is this legal? In spite of everything going on it may very well be but seems like they are taking advantage of this situation.

Thanks.