Our UKG son isn't reading sentences yet. Would that matter for class 1 at Vignan's World One in Ghatkesar?

His preschool is play-based. He knows his letters and sounds but isn't reading on his own yet, and some of the bigger schools seem to expect class 1 children to read short sentences from the first week. We're considering Vignan's World One for next June. Does anyone know how class 1 starts there? Is there an entry interaction, and do they expect reading by then or build it up through the first term?