There's a new vSphere 6.7 exam available for VCP-DCV from January 24th, presumably there will also be a 6.7 Foundations exam.
The latest information is here: It’s January…time for the new 2019 VCP certifications! - VMware Education Services
EDIT: In the comments of the above blog post, Karl Childs states:
"There will be a new Foundations exam for vSphere 6.7. However, it’ll be a couple weeks or so later than the VCP exam. Note that any of the 6.x Foundations exams will still count for the new VCP, so whatever works best with your timing and preparation."
In mind, but should I focus on the information in Foundation 6.5 or 6.7?