#1
I've been playing bass guitar and taking lessons for about a year and a half and guitar for just a couple months but I'm planning on switching the focus, I'd appreciate any advice on where to go from there and I've been going over wether or not I should switch lessons
#2
Switching/adding instruments would be facilitated by having a teacher help you through it.
Sturgeon's 2nd Law, a.k.a. Sturgeon's Revelation: “Ninety percent of everything is crap.”

Why, yes, I am a lawyer- thanks for asking!

Log off and play yer guitar!

Strap on, tune up, rock out!
#3
I did something similar about a year and a half ago, but in the opposite direction, adding bass guitar to the instruments I play. I didn't "shift focus," but simply added practice time. And lessons helped, though I needed to find an advanced teacher. Even though I was beginning on bass, I needed to learn techniques, not music.

I'd suggest continuing both together. You'll really begin to understand where both fit into the orchestration of a band, and if you can record yourself playing bass and then play along to your own bass lines, you'll be amazed at how quickly you progress.