In the course of a long, bloody war in Syria, a lot of territory has changed hands. The Kurdish YPG and their allies look to be the big winners, having carved out a vast autonomous territory called Rojava. Creating that territory was one thing, keeping it could be another.
Turkey is very openly hostile to the Kurds keeping any autonomous region. This is a major concern for the Kurds, as their gains were made with US support, and increasingly the US is realigning itself toward Turkey. This has Kurdish officials looking to realign themselves, potentially with the Syrian government.
Unlike most other breakaway regions, the Kurdish territory was never overtly separatist, and its split from the Assad government was mostly just a function of Syria losing all the surrounding areas. Negotiating a rapprochement, and the recognition of Rojava as an autonomous part of Syria, is now the Kurds’ top priority.
How that’s going to happen is unclear, but Kurdish officials are offering military support for Syrian military operations, suggesting they could send YPG fighters to join the offensive against Idlib rebels. Aligning themselves militarily is likely particularly key for the YPG, under the assumption that they’ll need help resisting Turkey’s invasion.