Where would one deploy deep space atomic clocks?

• Space.com: NASA IS LAUNCHING A GPS SYSTEM FOR SPACE
• NASA/JPL news: Five Things to Know about NASA's Deep Space Atomic Clock
• NASA mission pages clock
• NASA Deep Space Atomic Clock Fact Sheet

The first one is going to OTB, which is the Orbital Test Bed (quite cool!) rather than off-track betting.

Question:Once the technology matures, where would one deploy deep space atomic clocks? What is the long-term plan for deploying this technology?

fyi The von Kármán Lecture Series: 2016 Deep Space Atomic Clock is linked in How far from earth have atomic clocks (or ultra-stable oscillators) been placed and monitored?