When setting timezone to australia/sydney event in day calendar shows 30 mins late

Have you checked the actual strings that are produced by the date formatting code?

DayPilot doesn't make any adjustments to the date, it just displays what it receives.

yeah i checked, this
var date=moment.unix(value.appointment_date).format('YYYY-MM-DD')+'T'+moment.unix(value.appointment_time).format('HH:mm:ss');

and this new DayPilot.Date(date) both produces this date string :
2016-11-29T08:15:00 which i assume is a correct string?

Can you please give it a try with plain strings to see if it makes any difference? I would also check the startDate value (especially if it doesn't include the time part by accident). The latest DayPilot Lite release automatically strips off the time part but if you are using an older version it might have an effect.

You can also check the runtime values in the console:

// start date
dp.startDate
// events
dp.events.list

That should list the parsed values.

I tried by keeping plain strings too it doesnt work. But i found a workAround:
previously , i did this :
var date=moment.unix(value.appointment_date).utcOffset(11).format('YYYY-MM-DD') +'T' + moment.unix(value.appointment_time).utcOffset(11).format('HH:mm:ss');
var date2=moment.unix(value.appointment_date).utcOffset(11).format('YYYY-MM-DD') + 'T' + moment.unix(value.appointment_time).add('m',30).utcOffset(11).format('HH:mm:ss'); // i did this 2 make event only 30 m
then it shows 30 mins late.
but when i do this:
var date=moment.unix(value.appointment_date).utcOffset(11).format('YYYY-MM-DD')+'T'+ moment.unix(value.appointment_time).add('m',-1).utcOffset(11).format('HH:mm:ss'); //here substracting -1 to -30 works
var date2=moment.unix(value.appointment_date).utcOffset(11).format('YYYY-MM-DD')+'T'+ moment.unix(value.appointment_time).utcOffset(11).format('HH:mm:ss');

// this works but i don't understand why? Any explanation? is my method to show event for 30 mins (date2) wrong ? (making events.start and events.end 30 mins difference wrong?)

Can you please try to modify the following fiddle so that it reproduces the issue?

https://jsfiddle.net/urg6639x/1/