I expect Horford to continue to start and Timelord to come off the bench. The reason being Horford is still the most mobile and best perimeter defender of the trio so best equipped to deal with most PFs + his offensive game allows Porzingis to play inside more on offense whereas with Timelord, Porzingis will be forced more towards the periemeter.
G: Smart, D White
G: Jaylen
F: Tatum, Hauser
F: Horford, Muscala
C: Porzingis, Rob Williams
That is a huge amount of size on defense. Not just the twin shot-blockers but also the twin super-sized wings and 1-2 punch of big defensive PGs in Smart and D White. Super switchable perimeter guys. Loads of size and length. They are going to be very successful at shrinking the floor on defense with all that size.