Is Build 21 do 19+21

[Carl Oberman <swtrans@xxxxxxxxxxxxx>]

I had problems with TS 4.0.  I back it up using a network, but the backup
copy didnt work properly either so I decided to reload it and just copy the
backup over.  Still had the same problem (for some reason the thing went
nuts and added a bunch of space at the top of the charts).  Well I finally
found the problem in options, and fixed the space problem.

MY QUESTION IS THIS:

I have build 18 installed, your download site does not have build 19 or
build 20.  So when I downloaded build 21, does this automatically do build
19 and 20?