Canelo is expected to trigger his rematch clause against Dmitry Bivol and the WBC has given the green light for it to happen at 168lbs for their title.
Should the pair trade blows in the ring again then it'll take place on Mexican Independence weekend in September.
Golovkin was scheduled for that slot against Canelo and will now have to hope he takes the fight in December.
GGG returned to action earlier this year with a ninth-round stoppage of Ryota Murata to unify the middleweight division.
At 40, there are questions over how long Golovkin has left in the sport but according to Rob Tebbutt, he'll continue fighting until he faces Canelo.
"Gennadiy Golovkin - he could walk away from the sport now. He's had a fantastic career, 21 defences of a middleweight title and I know there's some consternation over the regular vs the full belt but he's had a fantastic career," Tebbutt told Planet Sport.
"He's made plenty of money but he's still not yet been beaten decisively yet. It's very rare you will see a fighter who is able to command a fee like he can and can command a purse like he can (and) leave the sport without being beaten decisively.
"Fighters stop fighting when people stop paying to watch them and people are still going to pay to watch Gennadiy Golovkin fight.
"And yes he lost to Canelo Alvarez and had a close fight against Sergiy Derevyanchenko but he's never been on his a**. Apart from the Derevyanchenko fight where he got hurt to the body, we've never seen him badly hurt or buzzed.
"It's usually fighters like him (that) leave on their back and he's not done that yet. I think we'll still definitely see Canelo-GGG fight because there's a lot of money to be made for both guys.
"After that it's anyone's guess. If Golovkin was to fight Canelo and get beat again then I think he'll probably call it a day there," said Tebbutt.
Outside of a Canelo third fight - to follow two bouts in 2017 and 2018, which ended as a draw and majority decision win for Alvarez - Tebbutt believes Chris Eubank Jr would be a good option for Golovkin.
The boxing reporter added: I wouldn't mind seeing him box Chris Eubank Jr I have to say - I think he beats Chris Eubank Jr at this stage but it's a much better fight than it would potentially have been years ago when it was first rumoured.
"I think Chris Eubank Jr would fancy his chances of beating this version of Golovkin but it's unlikely. You'll probably see Golovkin-Canelo either September or later this year at 168lbs."