While he has made himself available for the Magpies' Ranfurly Shield defence against North Otago at the end of the month, he still needs to complete his 14 days of managed isolation.
Head coach Mark Ozich said Falcon had shown versatility with "significant performances" in the first five, midfield and fullback positions, and Ozich is excited to see the "accomplished goalkicker" returning to the Bay.
"It's great to have Tiaan back in the black-and-white hoops as he will add valuable experience despite being so young and will certainly increase the competition within the squad for positions," Ozich said.
Hawke's Bay Rugby Union CEO, Jay Campbell, said Falcon was "an outstanding young man both on and off the field" who had already won a junior world cup, played Super rugby and two seasons in Japan and yet is still only 23.
"There is no doubt Tiaan is an exceptional talent and the Hawke's Bay public had only seen glimpses of that before he left, so I am excited to see him return to push for a place in the 2021 starting side."
Falcon is expected to make himself available for his club Clive in the remaining rounds of the Maddison Trophy once his stint in managed isolation comes to an end.
The Magpies' first game is a Ranfurly Shield defence against North Otago on June 30 at McLean Park, with their first Bunnings NPC game on Saturday, August 6, being an away match against Taranaki at Pukekura Park, New Plymouth.