Just had to cancel 2 return tickets for family travel this week & the online credit is only to 30 June. We will probably use this but can imagine there will be a real bun fight if some unable through no fault of their own, unable to use the credits before they expire. Doesn't seem reasonable & as you say a law change could add significantly to their problems.
I see SP currently up at 160 despite this new lockdown causing further major disruption. Seems to be a complete disconnect from reality.