SpaceX appears to be preparing to deorbit the Tintin Starlink demonstration satellites. The satellites were launched in 2018 and will be the third and fourth Starlink satellites to be deorbited.
Tintin A and B were launched aboard a Falcon 9 rocket on February 22, 2018, and were the first two additions to the Starlink constellation. The two test satellites were expected to remain operational for six months. If that operational lifespan was exceeded, the satellites would remain in operation until such time as the primary mission goals could no longer be met.
After more than two years in orbit, the two pioneering satellites appear to no longer be capable of meeting primary mission goals.
Since the satellites were deployed, they have remained in a steady orbit at an altitude of approximately 500 kilometers. Early this month, the orbits of both satellites began to shrink and are currently under 490 kilometers. This appears to indicate that the pair are set to be decommissioned in the coming weeks.
The decommissioning of Starlink 1220 was significant as it had been deployed less than a month earlier. This seems to indicate an issue with the satellite. However, SpaceX is yet to release a statement on any Starlink decommissioning conducted thus far. As a result, any speculation on the reasoning behind the deorbiting of Starlink 1220 would be speculation.