Best time to strike is when you're ready.
Once you have finances in order, research your desired area and start watching .... DAFT, MyHome etc.
Keep an eye on the Property Register and monitor the way prices are going/have gone in the area.
After Christmas seems to be a slow time for sales. I travelled the bye roads for a few years, watched the market, had my criteria laid out and when the ideal holiday home came up I pounced.
I went to see a property for sale, couldn't find it, enquired locally and was told about another property that was coming on the market ... went to it ... hopped a gate and bought it.