San Francisco (CNN Business) This year's 4/20 was shaping up to be big.

The high holiday honoring the cannabis plant was projected to draw record public celebrations and retail sales -- a reflection of the grassroots movement evolution into a burgeoning US industry. Plus, at 4:20 pm on April 20, 2020, it is the year of "four 20s."

This year's 4/20 will indeed be significant, but for different reasons.

As a result of the coronavirus pandemic, event planners have scrapped plans for large; outdoor gatherings; groups have organized online livestreams; and retailers have shifted expectations for a day that typically rang like Christmas to their cash registers.

"It's bittersweet, but we want to make sure everybody is safe," said Alex Aquino, whose Sounds Bazaar event business organized the annual 4/20 gathering on San Francisco's Hippie Hill, which typically attracts more than 20,000 attendees.

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