Short trips on the 4?

I havent ridden the A Division IRT lately, nor have I ridden the Lex-Jerome line in a long time. I was getting off a southbound 6 train today around 14:12, and I saw a uptown number 4 train of R142As with the sign displaying:

4: EASTERN PKWY EXP
4: LEXINGTON AV EXP
4: 149 ST GRND CONCOURSE

I didnt know they still did short trips on the 4..... I know some go to New LOTS as well as Utica. Where would this train go afterwards? Deadhead to Concourse yard?

According to the MTA Service Advisories page, there is no mention of any trains (weekend or weekday) that terminate service at 149th. (Weird?)

I would be asking the same question you did.

Could be an extra trip, maybe?