Drop down list returns variable number of values without blanks

I have a drop down list for a number of departments and it will return all the users in this department. The only issue is that some have many more than others so entering a row of text underneath means that it can be located way down the page with a lot of empty rows. Is there a way that the text will move down depending on how many users are returned? i.e. the easiest way that springs to mind is if all the users were to be returned in one cell below one another and the cell would expand accordingly.

Anyway, any help would be much appreciated.

Thanks in advance,

Alex

p.s. workbook is attached