Yes it may vary sir.
Even my experience of some train departing at 10.30,chart was published at about 9.30am.So you may work-about b/w 8-9am.
please wait...Translate to HindiHaan, yeh ho sakta hai boss.
Mere paas bhi tha ek train ke nikalne ka anubhav jo 10.30 baje ja rahi thi, toh uska chart kareeban 9.30 baje hi publish hua tha. Toh tum log 8-9 baje ke beech kaam kar sakte ho.