More than 3-4 days and it is recommended that you store under water rather than beer, bit like yeast washing but just to get rid of the beer rather than sorting the yeast/trub.
Two weeks under water is getting near the recommended limit for water storage to.
I'm sure you will get a bunch of people "she'll be righting" "I've done it heaps of times... but I'm pretty much quoting from Kunze, just happened to look up the reference earlier today.
Mark