Last day of class at the university: I arrive in the classroom I've taught in all semester to find that the table...

Last day of class at the university: I arrive in the classroom I've taught in all semester to find that the table with a prominent sticker reading "PLEASE DO NOT MOVE" and featuring a disability symbol has, you guessed it, been moved. What are my obligations? Move it back to its proper location, or obey the sign literally? And what does moving or not moving the table have to do with the ADA, anyway?