Yes, that’s correct.
And how wide?
I mean - storing it a bit diagonally tilted inside of the locker?
I believe that it is possible to save about 8 cm by detaching of saddle and carrier (this would be just two bolts + nuts.)
…and as above - I think it’d make sense if you tell a width - unmounting a saddle is not a problem here 
May I ask where you’re located?
Perhaps there’s a friendly Strida owner near you who would stuff her into your locker experimentally 