We will see what consequences this has. There is presently only one Soyuz capsule at the ISS and it needs to leave in December. By that time the ISS would be without crew because there is a requirement that a life boat is always present.

So if the issue is not solved by that time and any possible problem fixed the ISS will need to be abandoned temporarily. It is unclear how long it can fly untended. There is one potential alternative. They could send up a Soyuz unmanned and keep the present crew up for a major extension. That would give them until middle of 2019 to find and fix the issue.