UPDATE:
I figured it out. How I never saw the label setting for yes/no fields is beyond me.
We have a large number of Yes/No fields. Now our client wants to change the labels on the choices to something like /Yes - consuming service/ and /No - not consuming service/.
As far as I can tell, in the current version of Dynamics 365 there is no way to have a Boolean field with labels other than Yes and No.
It seems there may have once been two-option fields, but I don't see them in the current version.
Am I wrong? Is there a way to do what the client wants, without having to replace all those fields with Choices fields and changing every single calculation and form and so on?
Thanks for any help.