I saw this on a van yesterday morning.

Problem:
The apostrophe was in the wrong place, if the “Til'” — spelled T-I-L-APOSTROPHE — was meant to be a contraction for “Until”.

Explanation:
“Excelsior Learning Academy” appeared at the top of the sign on the van.

“Open Til’ Midnight” — with the apostrophe appearing after T-I-L — appeared immediately beneath the academy’s name on the sign.

Cross-referencing the telephone number, the multiply-named company actually seems to be a child-care center.

Discovering that Excelsior Learning Academy was essentially a child-care center answered my first question when I saw the sign: “Why would a ‘learning academy’ stay open that late?”

Perhaps this also explained the misplacement of the apostrophe for the omitted portion of the preposition “Until” when this so-called “learning academy” ordered a sign with a contraction for “Until”.

One might argue that Excelsior was creating a contraction of the preposition “Till” — spelled T-I-L-L — by dropping the final “l” and replacing it with an apostrophe, but I would counter-argue (1) that Excelsior and its sign maker probably were not that smart and (2) that it is a waste of an apostrophe to use it as a substitute for the similarly slim letter “l”.

Solution:
“Open ‘Til Midnight” or “Open Until Midnight”