Auto-Created Date field not displaying correctly.

Hello all,

I have a Cell that automatically works out and displays the date for the 1st sunday in the month depending on the date in cell B1:

=B1+MOD(7-WEEKDAY(B1,2),7)

This works like a dream and displays the date in the format i'm after which is:

yyyymmdd hhmm

Now, my main issue is when I try and add the date from the above formula into another (very long) formula. I've attached the code below, but the problem is when I use a cell reference to insert this date, it displays a random number (40790). I've changed the format of the cell containing the below formula to a date format, but it's making no difference

=IF(Diesel!A53="X", IF(Diesel!B53 = "","",CONCATENATE("ADD;HIERPRODSUBREFRESH;",Diesel!C53," - DIESEL;WEEKLY;",Diesel!$B$2,";",Diesel!J54,"")), IF(Diesel!B53 = "","",CONCATENATE("MODIFY;HIERPRODSUBREFRESH;",Diesel!C53," - DIESEL;WEEKLY;",Diesel!$B$2,";",Diesel!J54,"")))

The Cell reference that I am talking about is the one that looks like this: ", Diesel!$B$2,".

Does anyone have any ideas as to why the date is being shown perfectly in one cell, but whenever I try and reference it somewhere else it is shown as a random number?

Thanks in advance


- Jon