Edited June 5, 2020 to add: Loren Fishman has taken over Mallard Fillmore for at least the indefinite future. There is no word on when or whether Bruce Tinsley will return. There’s no news about Tinsley.
Mallard Fillmore is, my occasional jokes aside, not a strip I read regularly. So I am getting this second-hand. D D Degg, at The Daily Cartoonist, and at Usenet group rec.arts.comics.strips, reports on the strip. This week’s Mallard Fillmore strips are being signed “Fishman”. This after the strip has been in unexplained reruns since the middle of November 2019. No one has said publicly what’s happened with the strip’s creator and original artist Bruce Tinsley. And no one has said whether this is a temporary or a permanent gig for Fishman.
It’s also not quite confirmed who Fishman is. Degg says the general consensus is that it’s Loren Fishman, whose web site claims to have a blog and does not. I’d expect a gig in syndication to get a mention there. But the site does have a bunch of panel cartoons, some of them good, so maybe we’ll just see how this goes.