Residents and traders in Port Talbot fear the closure of the junctions would lead to the town being 'cut off' from business.
Steve Redmore, manager of Aberafan Shopping Centre, said the closure would restrict people coming into the town, which is not needed in the current economic climate.
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Swansea relieved the pressure on under-fire manager Bob Bradley with an emphatic 3-0 home victory over fellow strugglers Sunderland.
Sol Bamba was sent off after losing his cool but Cardiff hung on to claim a deserved 1-1 draw at Ipswich.
Today's rain will soon clear south-eastwards to leave a largely dry night with some long clear spells.