Reyes at age 31 had a 3.5 WAR, 104 wRC+, and .287 average (since BA was brought up by the smart poster who called everyone else stupid). The following season he fell off the face of the earth defensively and offensively. Tulo is clearly better than him, especially defensively, but age does not discriminate and Tulo's been average to below average offensively since the start of 2015. Now, if this hot streak is legit and he can carry it over to the 2nd half, then that changes things, but right now, I don't think it's fair to say "he is back". He could be, but hot streaks happen.
I'm in the camp that wouldn't mind trading him after this season, but a SS replacement has to be there (not Barney). With CWS's love of vets, maybe Tulo for Anderson is possible.