I arrived in CUN today - can confirm the timezone is now GMT-5, contrary to what my iPhone says, what the BA IFE map says and even what google says (they all think Cancun is still GMT-6). All very confusing! But the current BA flight schedule is indeed correct and flight time is 11hours. Captain told us the correct time as we landed but I wasn't sure whether to believe him until I saw proof on the clocks in the terminal.