The bot doesn’t even see the date, it just searches(in this case) for a mention of PayPal. And likely Ebay, Craiglist, etc.
How would a bot know to edit its post? 
Bot does some of the work, meatsack does the rest.
Paypal used to be very helpful, but I, too, find it annoying now. A few years ago, as I approached my $10,000 lifetime cap on something, they insisted that I do something like verify and/or link to my bank account. I refuse to do so, so I pretty much stopped using them. I think I have another $100 or so to go till I reach my cap, but after that, I’m done.
What I find really frustrating is that why would I become a greater raise of…whatever…after years of history with them? It would be the opposite. On the other hand, if they required verification or linking to a bank account based on size of transaction or someone who uses it a lot as part of their business, I’d have onto problem with that. It’s dumb and bad policy, especially since they are no longer the only game in town.