I've left one in the fridge for several years without doing anything to it but my fridge is at 3-4°C, not 5-6°C. You'll just need to wake it up and get it going again well before you need to use it and give it a couple of feeds before you make your sourdough from it.
It should form a layer of liquid over the top in time which may go a dark brown colour. It should smell fine, not bad if you get my meaning. There's nothing wrong with that colour provided there is no visible mould.
This is one that's been hibernating for a while now.
View attachment 95460View attachment 95461View attachment 95462
I'll need to wake it up and feed it several times before it is used, but the taste only improves in my experience with it.