This could mean anything, including him just having another appearance/cameo as batman written into some prior contract. I do love the trolling of Snyder stans though, even after Jim Lee outright said WB/DC were completely done with Snyder style DC movies, they keep doing little things to keep the Snyder stans pretending that they're
this close to "winning".
I mean, I do wish they'd stop giving them false hope because Snyder stans are really annoying. But I kind of enjoy the fact that Snyder stans are never getting another film in Snyder's style, and the DC film universe in general will basically have nothing to do with his movies going forward (and almost certainly just retcon all the unsuccessful stuff away when Flash eventually releases), but they're going to keep holding out a weird hope that DC will for some reason go back to a film style that underperformed and were generally horribly received by critics and general audiences. Its like sticking Snyder Stans in purgatory, but unfortunately we still have to hear them