The review window, after composing a message, presents the user with this prompt:
Send this email? [y]es/[n]o/[e]dit/[a]ttach
This does not reflect what keybindings might have been configured (or preconfigured) for, under the config section "[compose::review]". The preconfigured "p = :postpone<Enter>" is lost on novice users, which causes frustration when trying to make a draft.
A possible solution is to iterate over a user's "review" keybindings, and present them. Other solutions should be explored.