I found in one of my boxes I was doing a maintenance check on. Do I pull it to plant elsewhere or should I leave it since it’s in my box?

You could take it and move it along, does your box have good traffic? If it does than another boxer could take it along to a new box

I leave them for others to take and replant, but if you are traveling to letterbox, take it with you and replant. It's your box to do with it what you want!

Either way is OK. If it has been there a while and you are going boxing, take it and plant it elsewhere.
I would claim a find on it, too, both because it was found, and then the planter will know it's all right.

I don’t think it has been here long. It’s a fairly new box so it’s hard to say if it gets good traffic or not. Time will tell.

I would say that you should take it, after all you found it. It's yours to pass along. Your preference though, either way would work!
WW52

I decided to take it. I plan to rehide it very soon.