Likely due to Flair having had 4 aircraft repossessed, and they have a busy summer schedule approaching with those aircraft already on sale and flying allocated in the most profitable period of the year.
You might find that this ‘spare’ aircraft they have sitting around will no longer be a spare, perhaps that is now a luxury as the fleet orders with Boeing have fallen apart. The Canadian arm is under pressure now to ensure all lease payments are on time, otherwise we know what happens. 777 doesn’t appear to have injected any cash into it recently, as they only came to the party when a lessor threatened to take another 7 aircraft, then 777 stepped in and paid the bills overnight.
Commentary from Flair seems to indicate they are operating from its own reserves, which is using next months’ cash to pay last months bills. Virgin did that well.