Californians up and down the West Coast are knee-deep in preparation for the state's first 4/20 celebration after legalizing adult-use cannabis. But as pot shops up their stock and stoners practice fake coughs for Friday morning's sick day call out, the Golden State's hundreds of planned marijuana festivals, events, and public parties have had a significantly more stressful holiday season.

According to the Los Angeles Times, the California Bureau of Cannabis Control (BCC) has awarded at least 47 licenses for 4/20 events this Friday, where guests will be legally allowed to purchase and consume the plant and state-approved businesses can set up temporary retail booths. Outside of those approved festivals, though, the regulatory agency has made strict warnings that could see civil penalties for any licensed cannabis business participating in an unlicensed event.

"Any bureau licensee participating in an unlicensed cannabis event may be subject to disciplinary action," the BCC warning letter, released Tuesday, detailed. Adding, "Lawful participation by bureau licensees in any temporary cannabis event that allows sales and/or consumption is dependent upon issuance of the appropriate licenses from the bureau."

To complicate matters even further, California's adult-use legalization laws require the official support of not only the BCC, but also local regulators before any cannabis event can open its doors to the public. In Southern California, that multi-tiered system has already thrown a wrench in two of the areas most highly-anticipated 4/20 parties.

On Wednesday evening, the California City Council of San Bernardino rejected a permit application from High Times for the magazine's annual Cannabis Cup festival. Even with a letter from state pot czar Lori Ajax telling city leaders that the event would be approved for a BCC license with the council's blessing, city regulators voted unanimously to deny the public consumption and sale of marijuana at the three-day festival, which was expected to draw some 20,000 guests.

According to a report from NBC News, a representative from High Times present at Wednesday's City Council meeting decried a lack of "clear guidance," from the state, despite the BCC's pre-approval for the three-day event.

A few miles south in San Diego, the city's Bayked By the Bay festival will be held at a public park and not a country fair ground, excluding the event from even the possibility of a BCC license. Accordingly, Bayked By the Bay organizers have made it clear that marijuana will not be sold, consumed, or allowed in any form during the 4/20 celebration.

Since tomorrow marks the state's first 4/20 after implementing full-scale legalization, it is still not clear how law enforcement officers will react to unregulated public smoking events, from San Francisco's famous Hippie Hill smokeout to celebrations on college campuses across the state. As noted by Bayked By the Bay organizers, it is illegal to smoke weed in public places in California, but in past years, police officers have largely turned a blind eye to the mid-April holiday.

As for this weekend's High Times Cannabis Cup, event organizers told NBC News on Wednesday that they might consider refunding tickets if the public sale and consumption permits were denied. Now that this has become a reality, Cannabis Cup officials have not released an updated refund policy or plan for the weekend's festivities. As of press time, it appears that the event will continue as scheduled — just without any weed.

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