Future Historical Continuity

In Baen Books' seven-volume The Technic Civilization Saga, compiled by Hank Davis, Volume IV, Young Flandry, collects:

Ensign Flandry
A Circus Of Hells
The Rebel Worlds

In these novels, Dominic Flandry progresses from a nineteen year old Ensign to a twenty five year old Commander.

In my idea of a complete collection of Poul Anderson's History of Technic Civilization, Volume IV, entitled Young Flandry And The Terran Empire, would comprise: 

the Young Flandry Trilogy (see above); 
"Outpost of Empire";
The Day Of Their Return.

If we have read through the Technic History in chronological order of fictitious events, then we find that either version of Volume IV builds on the solid foundation of what has gone before:

In the Young Flandry Trilogy:
the Merseians return as a major threat;
the Gorzuni return as mercenaries;
Flandry scouts a planet lost since the Polesotechnic League;
Flandry and Djana travel in a ship with a Cynthian crew;
the Terran Empire bought the planet Llynathawr from its Cynthian discoverers;
we are shown the planet Aeneas;
the Aenean rebel, McCormac, seizes the planet Satan which belongs to the Duchy of Hermes;
one of McCormac's sons compares him to Manuel I;
Flandry compares the Didonians to the Togru-Kon-Tanakh of Vanrijn.

In the remaining two works:
John Ridenour returns;
we see what happened on Aeneas after McCormac's Rebellion and also learn more about Aeneas;
we get to see Aycharaych whom Ydwyr had mentioned;
an Ythrian spies on Aeneas.

These works also prepare the way for later events:

Flandry's and Tachwyr's careers will continue to progress;
Aycharaych and Chunderban Desai, both appearing in The Day Of Their Return, will return;
the predicted Fall of the Empire will happen.