OTTAWA -- In 72 hours it will be legal for adults in Canada to purchase, possess, or grow recreational cannabis, with some considerable caveats depending on which part of the country you live in.

On Wednesday, Oct. 17 the country will mark a historic moment: the end of the criminal prohibition on marijuana.

It also begins the 12-month march to edibles joining the list of permissible pot products -- the regulations for which Minister of Border Security and Organized Crime Reduction Bill Blair said are already in the works.

With the countdown to legal cannabis now measurable in hours, many retailers, police forces, and the general public are still curious and uncertain about how the rollout will go.

As part of CTV's Question Period special, focusing on the incoming major societal shift, Blair spoke at length with host Evan Solomon about where things stand, and why he thinks we're ready.

Though, even the president and CEO of cannabis producing company Canopy Growth Mark Zekulin admits there will be "hiccups for sure."

On the show, Zekulin said that while he anticipates a surge and likely more demand than supply on day one, it will take time for current users to pivot away from the black market.

Opposition critics also joined us to chime in on how they see the chips falling on Wednesday and in the weeks and months afterwards.

"This government is absolutely not ready for marijuana legalization. The country's not ready," said Conservative MP John Brassard, whose party has remained strongly opposed to the whole idea.

While the New Democrats are in favour of legalized cannabis, even NDP MP Alexandre Boulerice said "nobody is ready in the country."

Here’s a full rundown of what Blair had to say on CTV’s Question Period. For CTV News’ comprehensive cannabis coverage, click here.

What is the biggest outstanding challenge?

"It's a process of implementation," Blair said.

The federal government has been working for the last two-and-a-half years to implement what Blair characterized as a "very significant regulatory change." But he said that, at the end of the day, a lot of the responsibilities will fall on the provinces and territories, as well as the police forces within them.

Concerned about technological, training uncertainty?

Some police forces have been skeptical about using the new oral fluid testing devices to detect the presence of THC. Ottawa Police Chief Charles Bordeleau has said his officers won’t be using the first approved device, the Dräger DrugTest 5000, amid some reported concerns about its reliability.

Asked about that the uncertainty, Blair was blunt.

"Quite frankly I don’t know what scientist the chief in Ottawa has consulted, but I know who we've consulted and it’s the Canadian Society of Forensic Science's Drugs and Driving Committee."

Blair said that it'll be up to each police chief to determine how "he'll prioritize and deploy his resources," but cited a past call from Canadian police chiefs for new impairment detection technology.

"Some of them want to wait to see if other, you know, perhaps cheaper and easier-to-use devices come online and I anticipate that they will," Blair said.

As for the 833 Drug Recognition Experts (DREs) that are currently trained in Canada -- a number criticized as far too low -- Blair said there’s been a 60-per-cent increase in the last few years. While he admits more need to be trained, the number of DRE-trained officers is higher than it’s ever been.

Government officials told reporters at a background briefing on Oct. 5 that the plan is to have 1,500 more trained over the next five years.

Problem with the provincial patchwork?

While the federal law has set the overarching policy, lots of the specifics will vary from province to province, or depending on your region, possibly even from one city to the next. For example:

Most jurisdictions have opted to keep their legal marijuana smoking ages in line with those for drinking alcohol.

Bill C-45 allows individuals to grow up to four marijuana plants per residence, though some provinces, like Manitoba and Quebec, plan to ban home cultivation.

Provincial and territorial plans vary widely on whether you’ll be able to smoke in public.

Provinces and territories also differ on whether pot shops will be publicly or privately owned.

It's this variation that has led to lots of questions whether the federal government has done an adequate job communicating what the range of rules are, or whether come Wednesday Canadians will have issues appreciating the nuance of what’s allowed.

Blair said the regional difference in rules is fitting because it matches the differing circumstances across Canada, regarding the rules for alcohol, with an underlying consistency of the federal regulations.

"They are somewhat nuanced and different, but there is a certain consistency and all of them understand the importance of making sure this drug is not accessible to kids and they also understand the imperative of displacing the illicit market, and so there are differences, but those differences are appropriate to the context in which they’re being applied."

Will pardons be granted?

Blair said that as soon as marijuana becomes legal, it’ll be time for the government to turn to determining how they’ll deal with past simple possession convictions.

"That's the appropriate time to deal with those records and we intend to deal with them in an appropriate way," he said, though he wouldn’t elaborate on how soon after Wednesday their plans for these pardons could be announced.

Edibles regulations in the works

Blair said the government has already spent months working on the next round of cannabis regulations, which will make purchasing edibles legal.

Under the current law, you can make edibles at home, but packaged pot brownies, or going out for cannabis-infused cuisine for example, won't be commercially available.

"We understand the complexity of edibles and we want to make sure that we have the regulations in place to keep Canadian safe."

Concerned about getting burned at border?

Blair said he thought it was important that the U.S. border officials updated their stance on Canadians crossing the border this week.

Now, Canadians who are employed or invest in the legal cannabis industry should not anticipate any issues crossing the U.S. border, as long as the purpose of their trip has nothing to do with the marijuana industry.

Though, if travellers are coming to the U.S. for reasons related to the marijuana industry, they may be deemed inadmissible. As well, it remains illegal to bring cannabis across the border.

Blair said he hopes this answers some of the anxiety that investors or employees in Canada's cannabis business have been feeling, while reminding recreational users that any indication of marijuana use may still result in being denied entry.

"Do not lie, but at the same time you don’t have to incriminate yourself, you've got a choice: if you don't want to answer that question, you can turn around and head back in to Canada."

What kind of money will this make?

Asked what kind of revenue this new regime will rake in, and where that money will go, Blair said the federal government will only see the 25 per cent share of the excise tax with the provinces.

"That money will be reinvested in research, prevention, treatment, and rehabilitation and additionally we have proposed a certain fees system for licensed producers to insure that Canadians aren't paying the cost of the infrastructure that is necessary to administer that," Blair said.

Has there been enough education?

The federal government has allocated $36.4 million over five years for marijuana public awareness and education. Though some areas of the country just started hearing this week about how portions of that will be spent in their regions.

Blair said this isn’t the first time the federal government has thought about, or moved on, this piece of the new regime.

"We've been timing them to make sure we can inform people about the new rules, the new regulations, in a way that enables them to have the information that they need to make safe, smart, and legal decisions."

He said he’s been meeting with school boards across Canada about new curriculum, and cited the national anti-impaired driving ads that have been running.

A new national advertising campaign is also set to launch Oct. 17, centered on experts answering Canadians' cannabis questions. As well, all households across Canada are being sent a postcard that includes the most important information points about the new regime.

How long until every Canadian has a cannabis cabinet?

As happened over time with alcohol once that prohibition ended, it’s possible cannabis could become a household staple, much like many Canadians have some form of a liquor cabinet.

Blair said that’s not what he hopes happens. His aim is to have safe, healthy, and more socially responsible choices for their cannabis, while decreasing the number of youth getting high.

"It is not the intention of the government, it’s certainly not my intention to normalize the use of this drug," Blair said.