LIGO, Virgo and Kagra Observing Run Plans

The LIGO Laboratory Operations Management Team has reviewed procurements and operational protocols required for the Detector Improvement and A+ modifications in preparation for O4. We currently project that the O4 observing run will not begin before June 2022, due to key procurement delays. A number of significant modifications to vacuum and detector systems during autumn 2020 will refine our understanding of COVID impacts on our schedule. We will give a revised projection in March 2021 of the O4 start date, based on lessons learned.