The studio has a tentative plan to release a solo Batman movie in 2019 with Ben Affleck back in the cowl once again and maybe as director according to Latino Review. A working title is rumored to be The Batman but of course this is extremely early to speculate (doesn't stop anyone though) but if the timeline holds up then it would certainly make sense for such a release in 2019.
By then Batman V Superman: Dawn of Justice, Justice League and Affleck's other project Live by Night would be completed as well as the slate of rumored DC Comics movies. As long as it took the studio to sign Affleck it could have included some guarantees to direct with practical free reign and producing a Batman film would have been a good perk.
The talented actor and director still has a lot to prove for superhero fans as Batman but considering his recent success and attention to detail it's a good bet he'll be exactly what the character needs. As always things could change but it's a good sign that the studio is at least thinking ahead whereas before it was hard to tell what WB was thinking if at all.