What's too cold for WL400?

[codym]

I have been using my basement for storing all of my bottled beer. Normally it is at 65F and this has worked fine for my first couple batches. Lately it has been sitting at 58-62F and I just added two Belgian beers made with WL400 down there. Is this too cold? It says the ideal temp is more like 68-75 or so...Not a big deal to move them upstairs but I'm not sure where to put a 100 bottles. So I don't want to if I don't have to. Plus the 50 I'm bottling this weekend made with safe ale05