COVID caused passenger numbers to drop in the 10 days (approximately) leading up to the first lockdown and the suspension of services, to that end, the final day of "normal" operations was Sunday 8th March, give or take.
So if those above mentioned routes are indeed axed (I forgot Dublin, and excluding LCY as the Mayor is on record confirming it is only suspended), then they have been tried, judged and executed based on data from:
Alicante: Zero days
Cardiff: 20 days
Dublin: Zero days
Isle of Man: Zero days
Southampton: Zero days
Now regardless of what the reason or who made the decision etc, that is nothing short of unacceptable.