An Air Carrier pilot reported the Tower hours of operation for STT are not accurate in the Jeppesen Chart and company pages.

Narrative

We had been given TIST/STT as a precautionary alternate and were aware that according to NOTAM; alternate minimums are not available for the ILS and no non-emergency Company operations are allowed when the Tower is closed. The company pages as well as Jeppesen state this time as XB30L. The company pages add that the Tower may be kept open late with prior request. Due to various delays and a gate return for a medical issue we departed over 2 hours late. On descent into SJU we decided to ask SJU Approach Control to confirm. They indicated the tower at STT closes at XA30L. I realize we could have asked the Tower to stay open later in STT if we felt we might need to divert there but at this point we had our destination airport in sight so didn't ask for the extension nor did we have the time available to contact Dispatch for a possible change of alternate to BQN. We had plenty of fuel for any Puerto Rico alternate. We ultimately landed at XA15L in SJU but with an estimated flight time of 19 min from SJU-STT that would put us in STT at XA34L.Curious as to why the company pages/JEPPS could be off by a full hour; I later consulted an app called ForeFlight which indicated the Tower closes at XB30L but at XA30L during Daylight Savings Time which it currently was. Both the company pages and JEPPS application should be updated to reflect this important distinction.