My prediction of who EJ will take (so don't start shouting at me about my selections)
LH: Genge, Marler, Vunipola
HK: LCD, George, Blamire
TH: Sinckler, Stuart, Heyes,
LK: Itoje, Ewels, Launchbury, Isiekwe
BR: Lawes, Curry, Underhill, Dombrandt, Simmonds (50/50 on him vs Vunipola, if Binny is back in the EPS by then he'll tour), Chessum/Willis (depends if Willis gets proper time before then/if EJ wants the versatility of Chessum - could easily see Chessum being Lawes backup by then though)
SH: Youngs, Randall, Quirke
FH: Smith, Farrell
CN: Tuilagi, Slade, Marchant
WI/FB: Nowell, Watson, Daly, Furbank, Steward, Malins
Back three could change dramatically if some aren't fit (which is almost guaranteed with Nowell/Watson in there) but if everyone's fit I think that's who EJ takes
Furbank pips better options because EJ will have him covering 10 vs Tier 2
Backrow has the most question marks over it - there's a lot of options to choose from and EJ seems like he's going to cap even more over before the RWC
Scrumhalf could be JvP/Mitchell in the third choice if Quirke doesn't come back from injury on time/in good form