Moment add time zone offset for start end time

Question

Hello i am trying to add time zone offset for start & end date.

In order to get something like this

start date: Mon May 30 2022 05:00:00 GMT+0000 here offset is (00:00 + 5 hours US central time offset)

end time: Wed Jun 01 2022 04:59:00 GMT+0000 (23:59 + 5 hours offset)

But getting for start date Mon May 29 2022 00:00:00 GMT+0000

Here is my code

export function convertIsoToMomentLocal(iso: string | ParsableDate, timezone = 'CST') {
  if (iso && timezone) {
    const mo = moment.tz(iso, timezone).startOf('day')
    const offset = mo.utcOffset()
    const epoch = mo.add(offset, 'm').unix()
    console.log(epoch, 'test')
    return epoch
  }
}

So basically i am trying to determine start date and end date first, and only after that add time zone offset. Any ideas tnx, i have tried everything.