Greggs (LSE:GRG) shares have had the sort of month that turns short sellers into believers. A retreat on Friday left the stock up 21% for the month – so what comes next? In 2025, hot weather, higher employer National Insurance, and weak like-for-like sales growth all weighed on Greggs shares. Small wonder Greggs became one of the UK's second most-shorted stocks, with something like 12.5% of shares out on loan. Total sales were up 7.2%, but like-for-like growth was just 2.1% in company-managed shops (1.3% in franchises).