Your ignoring Riviera - there are four resorts on the line.
In the morning
Pop&AoA-to-CBR - Guests at POP&AoA going to HS PLUS those going to Epcot
CBR-to-HS - Guests at POP&AoA PLUS guests at CBR plus guests from Riviera going to HS
CBR-to-Epcot - Guests at POP&AoA PLUS guests at CBR plus guests getting on at Riviera (will need to leave some gondolas open) going to Epcot
Epcot to CBR - Guests from Riviera going to DHS.
In the Evening
Epcot-to-CBR - People staying at CBR & Riviera PLUS people staying at POP&AoA
CBR-to-Epcot - Guests from DHS going to Riviera .
HS-to-CBR - People staying at CBR PLUS people staying at POP&AoA & Riviera
CBR-To-POP - Pop&A0A Guest from HS PLUS POP&AoA guests from Epcot MINUS guests from CRB.
There are also people park hopping from Epcot to DHS and back. I'll also ignore you could get some Epcot area resort folks using the gondolas - For instance some folks from Beach Club / Boardwalk may choose to take the gondola to DHS instead of the boats.