I can reproduce the issue if I change "place only adjacent" to false in the config (Mod Options > Schematica > Config > Printer).
Tracked it down to Forge. On a non Forge server this does not happen, on a Forge server (and SP) the bug is present. Will see if I can figure out what exactly causes this to happen.
I re-checked my settings and i actually did have Place Only Adjacent to false. Whoops! Switching it fixed the problem. Thank you so much!