Zip Codes with Multiple DMAs OTA setup

I live in a zip code 21771, Mount Airy MD, which has multiple DMAs. The 21771 zip code is actually in 4 counties in MD, Frederick, Carroll, Montgomery and Howard counties. Frederick and Montgomery counties are in the DC DMA, and the Howard and Carroll counties are in the Baltimore DMA. When configuring OTA on the HR20 if I enter for my primary market 21771, I get the DC DMA, when I try to setup a secondary DMA and enter 21771 again; the setup comes back with DC again. With the HR10-250 when doing this I could choose Baltimore out of the list for a secondary market.

To make this work for me when setting up the secondary market I used 21776 as the zip code. This added Baltimore as the secondary market.

I’m not sure if I consider this a bug or not, as I believe there are only a few zip codes in the country that have multiple DMAs, and the work around is easy.

Maybe others with multiple DMAs and the zip code issue above could post their zip code and work around zip code.