I have to use a formula for due date in which there are constraints such as,
If item is of type I or type II, then,
{If an item arrives between 11:30 AM - 4:30 PM, it moves exactly after 4 hrs
from arrival.
If it arrives between 4:30 PM - 8:30 PM, it moves out the next day, 11:30 AM.
If it arrives after 8:30 PM, next day 4:30 PM.
If it arrives before 11:30 AM, 4:30 PM.
If it arrives on a Saturday, Sunday or on Friday after 8:30 PM, it leaves at
4:30 PM on Monday.
If it arrives on Friday after 4:30 PM, leaves on Monday - 11:30 AM.}

If item is of type III, then,
{If an item arrives between 11:30 AM - 8:30 PM, it moves out exactly after
24 Hrs.
If it arrives after 8:30 PM, 11:30 AM the next alternate working day.E.G.,
if at 9:30 PM on Tuesday, 11:30 AM on Thursday.
If it arrives before 11:30 AM, 11:30 AM next day.
If it arrives on a Saturday or Sunday or after 8:30 PM on Friday, 24 hrs
calculated from 11:30 AM Monday, i.e., 11:30 AM on Tuesday.}

If item is of type IV,
{If an item arrives between 11:30 AM - 8:30 PM, it moves out exactly after
48 Hrs.
If it arrives after 8:30 PM, 11:30 AM after 2 working day.E.G., if at 9:30
PM on Tuesday, 11:30 AM on Friday.
If it arrives before 11:30 AM, 11:30 AM next alternate day.
If it arrives on a Saturday or Sunday or after 8:30 PM on Friday, 48 hrs
calculated from 11:30 AM Monday, i.e., 11:30 AM on Wednesday.}

If item is of type V,
{If an item arrrives between 11:30 AM - 8:30 pm, it moves after 6 working
days, i.e., 144 hrs.
If it arrives after 8:30 PM or before 11:30 AM, 144 hours calculated from
11:30 AM the immediate working day.
In case of Saturday, Sunday & Friday after 8:30 PM, 144 hrs from 11:30 AM
Monday}

If item is of type VI,
{If an item arrives between 11:30 AM & 8:00 PM, it moves out exactly after
1/2 an hour from arrival.
If it arrives between 8:00 PM - 8:30 PM, moves at 11:30 AM next day.
If it arrives after 8:30 PM, 12:00 PM next day
If it arrives before 11:30 AM, 12:00 PM
If it arrives on a Saturday or on Sunday, 12:00 PM on Monday}

If there are any holidays, it should be incorporated.

Looks like a lot of IF functions. You might want to nest them, e.g.
If(A3="type I",If(...))
but you can only go so far - I think seven levels is the limit.

Alternatively (or in combination), with so many conditions you may be best
constructing some tables and using VLOOKUP().

"Revathi" wrote:

I have to use a formula for due date in which there are constraints such as,
If item is of type I or type II, then,
{If an item arrives between 11:30 AM - 4:30 PM, it moves exactly after 4 hrs
from arrival.
If it arrives between 4:30 PM - 8:30 PM, it moves out the next day, 11:30 AM.
If it arrives after 8:30 PM, next day 4:30 PM.
If it arrives before 11:30 AM, 4:30 PM.
If it arrives on a Saturday, Sunday or on Friday after 8:30 PM, it leaves at
4:30 PM on Monday.
If it arrives on Friday after 4:30 PM, leaves on Monday - 11:30 AM.}

If item is of type III, then,
{If an item arrives between 11:30 AM - 8:30 PM, it moves out exactly after
24 Hrs.
If it arrives after 8:30 PM, 11:30 AM the next alternate working day.E.G.,
if at 9:30 PM on Tuesday, 11:30 AM on Thursday.
If it arrives before 11:30 AM, 11:30 AM next day.
If it arrives on a Saturday or Sunday or after 8:30 PM on Friday, 24 hrs
calculated from 11:30 AM Monday, i.e., 11:30 AM on Tuesday.}

If item is of type IV,
{If an item arrives between 11:30 AM - 8:30 PM, it moves out exactly after
48 Hrs.
If it arrives after 8:30 PM, 11:30 AM after 2 working day.E.G., if at 9:30
PM on Tuesday, 11:30 AM on Friday.
If it arrives before 11:30 AM, 11:30 AM next alternate day.
If it arrives on a Saturday or Sunday or after 8:30 PM on Friday, 48 hrs
calculated from 11:30 AM Monday, i.e., 11:30 AM on Wednesday.}

If item is of type V,
{If an item arrrives between 11:30 AM - 8:30 pm, it moves after 6 working
days, i.e., 144 hrs.
If it arrives after 8:30 PM or before 11:30 AM, 144 hours calculated from
11:30 AM the immediate working day.
In case of Saturday, Sunday & Friday after 8:30 PM, 144 hrs from 11:30 AM
Monday}

If item is of type VI,
{If an item arrives between 11:30 AM & 8:00 PM, it moves out exactly after
1/2 an hour from arrival.
If it arrives between 8:00 PM - 8:30 PM, moves at 11:30 AM next day.
If it arrives after 8:30 PM, 12:00 PM next day
If it arrives before 11:30 AM, 12:00 PM
If it arrives on a Saturday or on Sunday, 12:00 PM on Monday}

If there are any holidays, it should be incorporated.