The former Saracens man has enjoyed a tremendous season for Bath, who reached the Premiership semi-finals before suffering a 35-6 defeat to Exeter Chiefs at Sandy Park last weekend.
However, Spencer – who has earned four senior international caps during his career to date – was not included in a second 26-man squad named by England that includes players from the beaten Premiership semi-finalists and will embark on another three days of training from Thursday (October 15) until Saturday at The Lensbury in London.
Instead, Jones is set to continue with Ben Youngs, Willi Heinz and Alex Mitchell as his available scrum-halves as the squad prepare for their delayed Six Nations clash against Italy in Rome on October 31.
While Spencer is left out, uncapped Bath team-mates Beno Obano and Tom de Glanville have both been called up by Jones, while Charlie Ewels, Jonathan Joseph, Will Stuart, Sam Underhill and Anthony Watson – along with props Joe Marler and Mako Vunipola – join camp for “reconditioning”.
In-form Worcester centre Ollie Lawrence is also in the squad.
Before facing Italy, England – who are without Sale centre Manu Tuilagi due to a serious Achilles injury – meet a Barbarians outfit in the uncapped Quilter Cup at Twickenham on October 25, while November brings matches against Georgia, Ireland and Wales as part of the newly-created Autumn Nations Cup.
“We had a good three day camp last week working on the basics and developing our cohesion as a group,” said Jones.
“This week the focus is to raise the standard as we continue our preparation for the Italy game.”