I don't want to force a retry just yet, I want to see when I should check the queue again. (Without having to mentally evaluate the retry configuration.) mailq only shows how long each message has been waiting, not how long until the retry time is reached. Is there a way to get exim to tell me when that will be?
exim ships with a utility, exinext, that will show you the first, last, and next retry times of a single message:
It seems that you could use exim_dumpdb and post-process the output, as exinext does, if you wanted to see information about the whole queue at once.