The message would say 'if your application was mailed after xx/xx/20xx, it has not been processed' - is that what you are looking for? I think they still do that, I called 2 weeks ago and still heard this
Ah I see! They don't post that online, that date is only available, I think, when you call IRCC.
Either way, that information is not super useful- they always say months behind, if you check the trackers, applications sent after the date they say are already being processed (some might not be).