A friend of mine, not in NUT but in a different one isn't striking. While she has many reasons for not doing so her chief one is that she can get tons of work done while everyone is out of the way!
I do understand while they're striking. If the retirement age increases to 66, as it will, but the pension can only be drawn at 70 (as is proposed) then they've got 4 years to "find" some money to support themselves. A tricky situation.
My solution would be to put retirement age up to 70 for everyone as of tomorrow.
Possibly not popular though?
All the best,
Spare