I have not gone after my BAT because I agree with Tx. There are many DC's in the ground that do not meet code any longer. Since 01/01/2009 there now needs to be a Isolation Valve and Wye upstream. Many of these DC's are slammed in to a narrow ROW as well.
Last year I went to Dallas to pull a permit. They kept wanting to see the drawings and I had to go meet with the plumbing manager. It took me 3 hours to pull a permit for the R&R job.
The inspector failed it. I called to find out why, because he wanted to the prints.
This tells me few people are actually pulling permits for DC R&R even if it is code and it has to be tested and inspected.