The worldwide fast-food chain explained that their delivery issues were due to, "teething problems".
However, Mark Rix, GMB national officer, accused KFC of "penny-pinching" and said the decision had not only cost 255 jobs at Bidvest, but had left workers at some closed KFC restaurants not getting paid enough.
The company started closing some restaurants on Saturday but has since reopened about 300 locations as of Monday, with no indication about when the remaining branches will follow.
"Hope to see you in our restaurants soon".
KFC has temporarily closed a number of stores across the United Kingdom due to chicken shortages caused by widespread delivery problems.
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KFC fast food restaurants in the United Kingdom are failing at their one job - to provide fried chicken to their customers.
The problem arose when it changed its delivery contract to DHL, which has blamed "operational issues" for the supply disruption.
The popular fast food outlet on Queen Street - the only KFC in the whole of Teignbridge - is one of hundreds of shops to be affected by the blunder.
It said it was encouraging franchisees to adopt the same policies despite operating their own contracts of employment.
KFC's chicken deliveries were up until February 13 managed by Bidvest, a specialist food distribution group.
"We are working with KFC and our partners to rectify the situation as a priority and apologies for any inconvenience this may have caused", a DHL spokeswoman said.