Ten members of the extended squad have been called up to the senior Springbok group for the clash against the Barbarians and the SA 'A' fixture against Zimbabwe in Gqeberha on 20 June, while Cheswill Jooste is still with the Vodacom Bulls, who have qualified for the Vodacom United Rugby Championship Grand Final.
The remaining 27 players will report for duty in Stellenbosch on Monday, while the players who are in the wider Springbok squad will rejoin the U20s upon completion of their senior commitments.
The Junior Bok training group consists entirely of players who have attended previous training camps in Stellenbosch, as well as the recent U20 International Series and the SANZAAR U20 Rugby Championship, both of which were won by South Africa.
Junior Bok captain Riley Norton (lock) is one of the players called up to Springbok duty, and he will be joined in Johannesburg by Oliver Reid and Danie Kruger (props); Siphosethu Mnebelele and Liam van Wyk (hookers); Vusi Moyo (flyhalf); Yaqeen Ahmed (flyhalf/centre), Luan Giliomee (utility back); Markus Muller (centre); and Zekhethelo Siyaya (fullback).
Jooste (wing) will only join later when he has completed his Vodacom URC duties with the Vodacom Bulls, while Kai Pratt (prop) was not considered for the camp due to injury.
The players released from Springbok and URC duty will join the Junior Boks before their departure to Georgia on Monday, 22 June.
Foote said the SA U20 group assembling in Stellenbosch from Monday would focus on fine-tuning their readiness for the global showpiece in Georgia.
"We are very excited for the players who have been called up to the senior Springbok group, and we have our contingencies in place as we continue with our final block of preparations," said Foote.
"Given the number of players called up to the Springboks, we have selected a wider training group for this camp in Stellenbosch.
"We are also pleased that we were able to give members of our extended training group game time during the recent U20 International Series and the U20 Rugby Championship. That gave us an excellent opportunity to continue building squad depth and cohesion, while also broadening our international experience."
Junior Bok wider training squad to assemble on Monday in Stellenbosch:
Props: Rambo Kubheka, Jordan Jooste, Luan van der Berg, Bongani Dlamini.
Hookers: Altus Rabe, Mahle Sithole.
Locks: Heinrich Theron, JD Hattingh, Jaythen Orange.
Loose forwards: Kebotile Maake, Risima Khosa, Luke Cannon, Wasi Vyambwera, Quintin Potgieter, Vuyo Gwiji, Gert Kemp, Thomas Beling.
Scrumhalves: Hendre Schoeman, Jayden Brits.
Centres: Ethan Adams, Samuel Badenhorst, Pieter van der Merwe.
Outside backs: Khuthadzo Rasivhaga, Jordan Steenkamp, Jack Benade, Alzeadon Felix, Akahluwa Boqwana.
Joining later (after URC/Springbok duties): Oliver Reid, Danie Kruger, Siphosethu Mnebelele, Liam van Wyk, Riley Norton, Yaqeen Ahmed, Vusi Moyo, Luan Giliomee, Markus Muller, Cheswill Jooste, Zekhethelo Siyaya.