Well, I’ve got a partial solution for you problem 
(I’m stuck on the duration as I’ve never played with that yet :winking_face: )
For your difference between your original {Star Date & Time} and the result you get in your formula, you might want to check the format of your field and see if checking/unchecking “use the same time zone (GMT) for all collaborators” solve the problem :winking_face:
If not (or if you don’t want to use the “same GMT for all collaborators”), you’ll probably need to add a SET_TIMEZONE() to the formula.
Using a Time Field included in a Date Field can add a level of difficulty/complexity when re-using it elsewhere.
That’s why I used a DATETIME_FORMAT() function in the formula I tried and seems to be near what you want :winking_face: .
I used an & though instead of CONCATENATE()
' -- '&DATETIME_FORMAT({Star Date & Time},'YYYY-MM-DD')&' T '&DATETIME_FORMAT({Star Date & Time},'LT')&'\n -- '&{Description}&'\n -- '&{Duration}
For the {Duration}, Effectively {Duration}/3600 (as the concatenation of the duration field appears to be in seconds) give 2,5 as result… And I’m actually kind of stuck there (sorry) 
Add-on :
I’ve searched the community a little bit for the {Duration} field.
The easiest solution I’ve found would be to create 2 Number fields formatted as integer :
{Hours} : for the hours in {Duration}
{Minutes} : for the minutes…
After that, it’s pretty easy to integrate those 2 fields in the formula :winking_face:
' -- '&DATETIME_FORMAT({Star Date & Time},'YYYY-MM-DD')&' T '&DATETIME_FORMAT({Star Date & Time},'LT')&'\n -- '&{Description}&'\n -- '&{Hours}&'h '&{Minutes}&'m'
You format date and time fields using a function with the clever mnemonic of DATETIME_FORMAT() :winking_face: . The precise format is determined by the format specifier used.
For the duration, as far as I know, you’ll have to hand-craft a formatting routine yourself. Duration fields are stored internally and expressed in formulas as seconds, so a formula to display a duration in '#h ##m' format would be
IF(
{Duration},
IF(
{Duration}>=3600,
INT(
{Duration}/3600
)&'h '
)&
REPT(
'0',
2-LEN(
(INT(
MOD(
{Duration},
3600
)/60
))&''
)
)&INT(
MOD(
{Duration},
3600
)/60
)&'m'
)
(That gives you one or more hour digits followed by 'h' and a space, followed by yalways] two minute digits sleft-padded with '0' for values less than 10] followed by 'm'.)
You format date and time fields using a function with the clever mnemonic of DATETIME_FORMAT() :winking_face: . The precise format is determined by the format specifier used.
For the duration, as far as I know, you’ll have to hand-craft a formatting routine yourself. Duration fields are stored internally and expressed in formulas as seconds, so a formula to display a duration in '#h ##m' format would be
IF(
{Duration},
IF(
{Duration}>=3600,
INT(
{Duration}/3600
)&'h '
)&
REPT(
'0',
2-LEN(
(INT(
MOD(
{Duration},
3600
)/60
))&''
)
)&INT(
MOD(
{Duration},
3600
)/60
)&'m'
)
(That gives you one or more hour digits followed by 'h' and a space, followed by yalways] two minute digits sleft-padded with '0' for values less than 10] followed by 'm'.)
Thank you very much @W_Vann_Hall for the {Duration} !
I was really curious about the formula for that, as I couldn’t get near there no matter what I tried 
Just in case, in its entirety with the big help of @W_Vann_Hall 
, the final formula should look like something like this then 
' -- '&
DATETIME_FORMAT(
{Start Date & Time},
'YYYY-MM-DD')
&' T '&
DATETIME_FORMAT(
{Start Date & Time},
'LT')
&'\n -- '&
{Description}
&'\n -- '&
IF(
{Duration},
IF(
{Duration}>=3600,
INT(
{Duration}/3600
)&'h '
)&
REPT(
'0',
2-LEN(
(INT(
MOD(
{Duration},
3600
)/60
))&''
)
)&INT(
MOD(
{Duration},
3600
)/60
)&'m'
)
This is great! - thank you so much @Ptt_Pch and @W_Vann_Hall. Thanks for both of the detailed replies, so helpful.
The use same time zone GMT fixed the 1hr time shift issue. The formula also displays the date as I need.
The formula to get the duration works a treat, so much logic to follow there.
Thanks for putting it all together too.
Both so helpful. Many Thanks
Thank you very much @W_Vann_Hall for the {Duration} !
I was really curious about the formula for that, as I couldn’t get near there no matter what I tried
Just in case, in its entirety with the big help of @W_Vann_Hall , the final formula should look like something like this then
' -- '&
DATETIME_FORMAT(
{Start Date & Time},
'YYYY-MM-DD')
&' T '&
DATETIME_FORMAT(
{Start Date & Time},
'LT')
&'\n -- '&
{Description}
&'\n -- '&
IF(
{Duration},
IF(
{Duration}>=3600,
INT(
{Duration}/3600
)&'h '
)&
REPT(
'0',
2-LEN(
(INT(
MOD(
{Duration},
3600
)/60
))&''
)
)&INT(
MOD(
{Duration},
3600
)/60
)&'m'
)
@Ptt_Pch 
High five!
@Ptt_Pch High five!
Ahahah 
!
High five @W_Vann_Hall !
(I didn’t do much though :winking_face: but I learned a lot with your formula )
@copal I’m glad to know I could help a little and that this works for you :winking_face: !
Big help @W_Vann_Hall & @Ptt_Pch - Thanks Again! :thumbs_up:
You format date and time fields using a function with the clever mnemonic of DATETIME_FORMAT() :winking_face: . The precise format is determined by the format specifier used.
For the duration, as far as I know, you’ll have to hand-craft a formatting routine yourself. Duration fields are stored internally and expressed in formulas as seconds, so a formula to display a duration in '#h ##m' format would be
IF(
{Duration},
IF(
{Duration}>=3600,
INT(
{Duration}/3600
)&'h '
)&
REPT(
'0',
2-LEN(
(INT(
MOD(
{Duration},
3600
)/60
))&''
)
)&INT(
MOD(
{Duration},
3600
)/60
)&'m'
)
(That gives you one or more hour digits followed by 'h' and a space, followed by yalways] two minute digits sleft-padded with '0' for values less than 10] followed by 'm'.)
Thanks - this is brilliant and solution I have been looking for. How would this look if expanded to include seconds as well as hours and minutes? I’m trying to decipher it but having trouble.
