Looks like it is still bugged on the PBE right now, so there is definitely no fix coming in 10.16 and I don't even think it is on the radar right now.
Maybe u/AzuBK, /u/riotphlox or another Rioter could fix/forward it if they read this. Otherwise, maybe try reaching out to a dev on Twitter. In that case, if you get an answer (or don't), message me again!
I'm not in the office today (whatever that means nowadays...), but I'll make sure QA is aware of this bug so we can get it fixed.