24 hours or less for ponding test is good enough
The ponding test required 24 hours practice is good enough to determine good waterproofing or not.
The idea is like this, nobody showering more than 24 hours with the water ponding the whole floor. Each time ppl shower, the water discharge to the downpipe and dry within an hour.

2 days is possible with 2 coats waterproofing + 24 hours ponding test
Due to less ventilation in toilet, the 1st coating waterproofing may take longer to dry compare 1st coating at outside exposed to the hot sun.
It depends the your shower ventilation condition. To speed up the process get a standing fan blow it.
If your contractor able to time this work well, he can apply 1st coating on late evening (same day he completed concrete hacking), let the overnight 1st coating cure and proceed with 2nd coating the next day. In the end it just took 1 day only.

4 days (waterproofing + ponding test ) is possible subject to factors.
2 days (waterproofing + ponding test) with 2 coatings and 24 hours ponding test is possible too but with good planning.

Curious can you share what waterproofing solution did you use previously and the leaking return again after few months? You mention dripping, is it a continuous dripping even without using the shower?
This is true, depend the toilet size, overall complete process it takes 6-7 days averagely for a typical size toilet.

Non-hacking waterproofing not recommended as it delays the problem and not solving the root cause.
This is also true especially the water repellent waterproofing, sealing between the tile joint, and other marketing gimmick waterproofing products.
why?
Most of the chemical will eventual wear out, less effective after months or 1 - 3 years (depend the concrete structure, how frequent usage of shower area). It only serve as temporary solution.
Imagine the rain repellent chemical you apply on car windscreen.

It also subject to the contractor knowledge method how to solve the given problem.
Only PU injection can fix from below. Always be ready that PU injection might need 2 or 3 times to fix the leaking. This is important when you discuss the warranty term. Best to have the contractor to warranty the whole area. Example your leaking area is toilet, ask the contractor to give warranty the whole toilet area in the event new leaking appear.