Pac-12 athletic directors are targeting Oct. 31 as the preferred start of the football season, pending approval from the presidents and subject to the easing of local health restrictions, according to conference sources.

“It might be a challenge, but many of us would like to play then,” said a source familiar with the decision-making.

“We think it’s possible.”

That date would place the conference one week behind the Big Ten but give the Pac-12 champion eight total games and possibly open a path to be considered for the College Football Playoff.

There are three obstacles to the season beginning on Halloween, sources said:

— Navigating the last batch of local health restrictions

— Gaining consensus on the training camp schedule

— Approval from the CEOs

The presidents and chancellors are gathering Friday for a meeting that was scheduled prior to the momentous developments Wednesday.

Basketball was the original focal point, but the football restart will be discussed in depth with a possible vote on a date to begin the season.

Once that date is set — if a date is set — the training camp calendar will be established.

“They have to designate that they’re going to have a season and pick a start date before everything else can be formalized,” a source said.

The conference medical advisors believe players need six weeks of preparation, with a two-week ramp period followed by four weeks of full-contact training camp and practice.

There is some discussion within the conference about shortening the period of preparation to five weeks.

However, several sources expect the presidents to lean on the medical advisors for guidance, pointing to a total of six weeks.

Crucially, the ramp period could begin before the daily antigen testing programs are up and running, according to sources. That would help accelerate the start of camp and the regular season.

However, each team must meet the testing standards established by local health authorities — standards based on the prevalence of the virus in the community.

(Some teams might have to test daily; others might be required to test once a week.)

The PCR tests that have been in use through the offseason, and have a 24-to-48 hour turnaround time, would be used during the ramp period.

Full contact work — the heart of the preparation — would not begin until the daily antigen tests are available at the end of the month.

The timeline could require the presidents to solve a potentially vexing issue:

Will they allow each team to begin the two-week ramp period when ready, or stipulate that everyone move forward collectively?

The Los Angeles schools have received the clearance they need to practice, but the Bay Area schools are still working with their authorities.

For the season to begin Oct. 31 and teams to have a full two-week ramp and four weeks of contact, the presidents would need to approve the restart on Friday.

Multiple sources indicated contingencies could be included with any decision, based on the lifting of health restrictions.

In other words, even a vote to restart could include some ambiguity.

Whether they aim for Oct. 31 or Nov. 7 — the most likely dates, by far — the schedule itself must be crafted around a Dec. 19 championship game.

Six or seven games?

A bye week or straight through?

How will cross-division opponents be determined? Will competitive equity be considered?

“That’s where the rubber is going to meet the road,” a source said. “The ADs just want to play and not get caught up in equity.”

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