I just got mine feeding after 5 months also.... damn cold, happens every year.. I need to move to Qld haha
The only loss of condition I noticed was obviously weight loss, but also his sloughs since he stopped feeding have been terrible. Never a problem with a good diet. It's also handy having other hungry snakes when you know ones more than likely going to refuse a feed. Nothing worse than throwing money away. Having said that my Bredli and Water Pythons have never refused a feed regardless of weather.
I find the best way to counter the weight loss is fatten them up over summer, it's a pretty natural cycle. Only seems to present problems when snakes go into the winter already on the thin side.