Past works by Shipton have centered on ideas of urban scenes, language, and attempts to process information. In 2020 and during the darkest days of Covid-19 the artist reworked her 2014 "Exit Sign series" in a work titled “Frontera 1845”. Here, the images are reordered to place Cotulla at the center of the seven signs. In 1845 the US-Mexico border was the Nueces River and not the Rio Grande. The first U.S. town after crossing the Nueces River is Cotulla, a significant place for the artist personally and socially as it was also an inspiration on Lyndon B. Johnson Civil Rights Act of 1964. It was in Cotulla where Johnson spent a year teaching grade school students, in 1928, provided him with his "first lessons in the high price we pay for poverty and prejudice," and inspired his later work with civil rights and higher education opportunities for all Americans. Johnson carried his experience in Cotulla with him for the rest of his life.