1. They're trying to untangle a snarl-up in editing.

2. Bottleneck noun block, hold-up, obstacle, congestion, obstruction, impediment, blockage, snarl-up (informal, chiefly Brit.), (traffic) jam a town-centre Bottleneck Collins Thesaurus of the English Language – Complete and Unabridged 2nd Edition

3. Bottleneck noun block, hold-up, obstacle, congestion, obstruction, impediment, blockage, snarl-up (informal, chiefly Brit.), (traffic) jam a town-centre Bottleneck Collins Thesaurus of the English Language – Complete and Unabridged 2nd Edition