Looks like the bookstore is closing early too.

Literal

Bookstore [also-も] early-closing [seems-のようです].

本屋さん uses the affectionate さん suffix on a shop name — common in casual Japanese. おそじまい is お早じまい, a polite form of 早じまい 'early closing.' ようです expresses inference from observation: 'it appears to be.' A quiet everyday observation.