NOTE: This question was originally asked about "Inbox by Gmail", when it existed, but Inbox has been retired and its Snooze feature rolled into Gmail. This question now applies to the Snoozed messages in Gmail.
Pending the shutdown of Mailbox from Dropbox, I'm exploring other apps that can offer the same kind of message postpone features. Gmail
Inbox with Snooze is pretty close, except I also would like to access the "snoozed" emails via IMAP. (I'm writing the code, so it could be either IMAP or Gmail API.)
Is there a way to get the list of "snoozed" messages for Gmail
Note that I'm not optimistic at this point, because this recent feature request for an email client requests the same thing, and the author (who probably knows more about the Gmail API than I do) says it's not possible:
Unfortunately, we can't support the categories in Google Inbox because they aren't exposed via the Gmail API or the Gmail IMAP interface. They're only available from Google Inbox itself.
I am also aware of How to find an email in Gmail that was snoozed in Google Inbox? which shows how to view snoozed emails from the traditional Gmail interface, but I can't seem to apply the same approach to IMAP.