It looks like they are, indeed, planning to go on, with Francis on bass, as noted in this article on Ultimate Classic Rock:
Been a fan as long as I’ve been a rock fan. El Loco dropped when I was in high school, and I was so proud of myself for figuring out on my own what Pearl Necklace was really about - and I turned out to be right!
Saw them fairly early in the Eliminator tour, before the album really blew up. At the time (June) only one video and single had been released, so it was mostly older fans. In one of the weirder record label forced pairings I’ve seen, Quiet Riot was the opening act.
Saw them again on the Afterburner tour, where they seemed bored and going through the motions on MTV hits, but really enjoyed themselves on the older deep cuts like “Arrested for Driving While Blind” and “Jesus Just Left Chicago”
Being from Houston, I’ve seen them more than any other band. I was thankful to see them at the the closing of The Summit, which I believe was the first place I ever saw them, too. The Summit became Lakewood Church, of Joel Osteen fame. (Boo, hiss.)
They are iconic, and not called that Little Ol’ Band from Texas for nothing. RIP Dusty. The great Rock and Roll band in the sky just gained another awesome bass player! You will be missed.
Leland Sklar would be an ideal choice for bass. He’s toured with Toto, Phil Collins, and James Taylor. He’s a session player with a huge discography.
Best of all is the beard. He hasn’t seen a razor since the late 60’s.
That is good to hear.
He looks the part. But can he play the Boogie? 
(never heard a Boogie by Toto, Phil Collins or James Taylor…)
If there’s ever an occasion where one wishes to be Sharply Dressed…
Hehe, their genius as a band is that they never took themselves seriously. That let them do a lot of things other rock bands wouldn’t try, both musically and in their stage show. It also probably is what made Hill and Beard not bat an eye when they were mostly replaced by synths on Eliminator. They just learned how to reproduce the parts for the live show, and went on being ZZ Top.
I teared up when I found out he’d died. Gonna miss ya, sir. I always preferred your voice to Billy’s.
Fil (Wings Of Pegasus) analyzes ZZ Top live in 2013.
He’s a good dude, has a good channel, would recommend.
I first got acquainted with ZZ Top strangely enough by watching World Class Championship Wrestling as a kid. La Grange was Kevin Von Erich’s entrance music. A lot of my grade school classmates at the time were into ‘rasslin’ and of course we’d all get amped when that song came on.
No idea why, but I’ve always liked TV Dinners. The video’s funny.
Just found this. These guys really rocked.
I’ll watch that later, when I’ve gotten a few more beers in me!
Here’s a statement from Dusty’s widow.
ZZ Top is…Texas.