Think it might be more a misunderstanding of my question.... As it stands, the rebooking process has to be undertaken over the next week or so. According to the FAQ:

”A fare difference may apply. Changes should be made no later than 25th March 2020, and some terms and conditions apply.“

Like many others, flights were booked to travel to a specific event or meeting, and it will be far from clear over the next week when those events will be re-scheduled to. It’s not so much About getting flights for a specific date some time in the future, but simply that the date that many customers will need to re-book for is completely unknown And will remain so until well after the limited window within which the flights can be changed, expires.

At the moment, I have no idea when I will need to change my flights to. Best estimates I have is that the new timing will not be clear for at least twelve weeks. In those circumstances, what might the best mechanism be to preserve the flight value, vs losing it all to cancellation? The equivalent schemes on alternate carriers (e.g. trade in for a 12 month travel voucher of equal value) seems a lot easier to administer...

I’m sure my situation is not unusual...