Goodmorning Joan, the washing temperature is the same for every water based and plastisol inks: the standard temperature for every screenprinting ink is 60°C. In particular for plastisol inks composed by metal powders, as gold or silver, it's important suggesting to turn inside out the tshirts before washing it.
For plastisol inks you haven't to wait: you can wash it as the ink is cold. For water based inks ypu have to wait 96 hours: during this time ink continues drying. Adding a catalyst or drying it into the oven could shorten the waiting time, but it's hard to say how, so I think that write on the label to wait 96 hours it's a very careful advise.

This is Franco Ratto,