Oviedo Hiking

Hello,I would like to ask an advice.Basically for a peace of mind I had to booked extra days even knowing that I will do the San Salvador in less days,but could not risk to book a flight later during the camino e find expensive flights back.So basically I would like to ask once I get to Oviedo ,does anyone knows if It is easy to for example walk maybe 3stages of the Primitivo and from there catch a bus to go back to Oviedo the day before my flight??Other option are all the hiking near Oviedo( las Xanas,senda de el oso,picos de europa, las Ubiñas)but it seems not that well connected by bus and I don't want to rent a car by myself and taxis are really expensive and I am on budget?Any tips,advice,others group suggestions are appreciate,can be spanish forum as well . thanks in advance to everyone