After Radcon becomes touch dry the first watering is absolutely critical.
If the product is not watered within a few hours after becoming touch dry the system is lost and the Radcon material is no more useful than a silicate floor hardener.
The day 2 and 3 waterings can be conducted at any time in reality. The fact is it will usually take about 3 waterings over 3 days to achieve sufficient Radcon growth in cracks to achieve a 100% watertight result.
Once Radcon is touch dry you cannot water it too much.
In fact you could dam the area and allow the cracks to leak water until they totally seal 2-3 days hence.