Lining work is quick because there is no groundwork. The pipe is cleaned and jetted, surveyed, measured, the liner is prepared on site and installed, and after curing the run is re-surveyed. Water can normally be used again the same day.
Excavation is slower because of the groundworks around it — breaking out the surface, digging to depth, shoring where needed, replacing the pipe, backfilling in compacted layers and reinstating the surface. Reinstating block paving or a concrete drive can add a day.
Whatever the method, insist on a start and finish estimate in writing before work begins, and on a post-repair CCTV recording afterwards.