Service tax on transport of goods by road

Dear All,

As i understood that outward GTA service is not elegible for Cenvat credit. but when GTA service provider providing the services on continuous basis, accrodingly freight paid on both outward journey with goods and return without goods. (both outward and return from the place of removal and upto the place of removal respectivly)

Fregiht charges specified for the return journey without goods, Is it falls under perview of GTA services.  Is it required to pay ST on return journey also. if it is so, will elegible for Cenvat retun journey???

Thanking you, in advance