Some Blueprints Won't Go in Guild Bank
Are you sure you don’t have them in invisible bags? I don’t have any problem placing Arrow Cart, Ballista, Alpha Siege Golem Blueprints in my Guild Bank.
You could always destroy items you don’t want to save, if they become to inconvenient. Or purchase (with Gold) more bank slots. Totally up to you, of course.
Good luck.
I just solved the problem of the items not going into the guild bank.
Interestingly, I got the issue when I pulled trebs out of the guild bank to begin with. When I tried to put them back in, there was a red box in the slot I was trying to place them and they would not go in. Additionally, I was not able to mail the trebuchet plans to anyone either. The only option I saw when I right clicked the plans was to destroy. I could put them into my personal bank, so the game was treating these as account bound items.
Now, on to the solution… I found one plan in a personal bank spot and put it into my inventory. Then, I confirmed I had more options, such as mailing, when I right clicked the plan. Following, I put the stack of problem plans onto the one that worked in my inventory and confirmed the same options when right clicking. After doing this, I was able to put the plans into the guild bank.
I do think this is some sort of glitch and not necessarily tied to any specific type of plan based on the inconsistency seen in above posts.
It’s a visual glitch related to syncing the display of contents in the guild bank and your inventory: it’s reasonably common when items are removed from the bank that they can’t be seen in inventory (and less often, vice-versa). The item is still there (as can be seen if you try to move another item on top of it).
This almost always resolves itself if you move another item from (or to) the guild bank, although sometimes requires moving one more item.
It’s more noticeable in banks shared by a lot of players, especially during peak periods of use.
tl;dr it’s a visual glitch, not a binding issue and resolves itself eventually
(still: it’s horribly annoying when it does happen)