Judging from the demand curves published on the National Grid web page and present storage level (4 000 million cubic meters) and that present flow into UK is running steady at 300 million cubic meters a day, it could be that storage facilities could be emptied by second half of February under normal weather (consumption) conditions.
Personally I don't give any credibility to weather forecasts more than two weeks out, however your mention of February reminded me of the NetWeather winter forecast:


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They are suggesting February could be the coldest since 1991.

Hi all, my first post after lurking at TOD and TOD UK for ages! Great work you are all doing. The gas graphs are interesting and I thought I'd just ask a question... we are connecting around 100,000(?) properties to the gas mains each year in the UK - primariliy as a result of new builds, so wouldn't you expect to see constant rising demand for gas? (or do changes in demand for electricity generation, industry etc swamp any domestic use changes?)  I suppose on the negative side of things, every 5% rise in fuel prices results in a further 30,000 households being pushed back into fuel poverty and reducing their use of gas and electricity. And fuel prices have gone up by more than 5% over the last year. Regarding the weather - it has certainly been mild until a week or so ago in Scotland, where I am, and at work the office delayed switching on the gas boiler by a month  (though it was burning through the gas on Friday - what with it snowing outside!).