"Stable beams" has been declared 30 minutes ago. Similar to 2016, the initial collision rate is low (0.2% the design rate). The machine operators have to check that everything works and nothing presents a danger to the machine before more protons can be filled in. It will probably take a few weeks to reach the same collision rates as achieved last year. Meanwhile, the experiments start collecting some initial data. 0.2% sounds like nothing, but for some analyses this is ideal. The LHC experiments are not only limited by the number of collisions, they are also limited by the amount of data they can read out and process. This is about 1 kHz for ATLAS and CMS (about 13 kHz for LHCb, 200 Hz for ALICE). At the design values, this means 99.9975% of all collisions are discarded: Only the most collisions with the highest particle energies can be kept. The other collisions are still interesting, however. Currently the high-energetic collisions are rare, which means there is more space to record other processes.