Eddie Jones is expected to name a maximum of 40 players in England's full World Cup training squad on Thursday.
Saracens and Exeter's big guns will be rolled back in for England's third training camp ahead of the autumn's Japan tournament.
Head coach Jones is understood to be keen to keep his training numbers tight, in a bid to avoid any hefty late whittling down to the final 31-man World Cup squad.
The deadline for submitting that final World Cup roster is September 2, with England starting their campaign against Tonga in Sapporo on September 22.
Ben Spencer is expected to slot into England's scrum-half options, which could leave one of Gloucester's Willi Heinz or Wasps' Dan Robson vulnerable to dropping out.
Danny Cipriani will be among those eager to stay on at Pennyhill Park, having only joined England's World Cup preparations last weekend.
The Premiership player of the year and players' player of the year was rewarded for a stellar first campaign with Gloucester with a surprise England call-up last week.
But the return of captain Owen Farrell, and the expected addition of playmakers – like Alex Lozowski and Henry Slade – might squeeze out the in-form 31-year-old.
Kyle Sinckler was excluded from last week's 34-man training group, sent back to Harlequins for treatment on a minor hamstring complaint.
The British and Irish Lions prop will face a nervous wait to discover his fate too, as to whether he will be recalled now or told to continue working on his injury at his club.
