Its main employer is about to shatter into unfamiliar pieces. Its industry is on the outer technological frontier. So today the Communications Workers of America did an extraordinary thing for a labor union: it moved at a special convention here to restructure itself for an uncertain future.

Futurist Alvin Toffler set the stage with a sobering keynote address. "The hard truth" about the decline of unions in recent years "is that the labor movement has not adapted to new forces. Above all, it has not anticipated the fast arrival of the future," he told the more than 1,500 delegates from around the country.

In a world reeling from the speed of change, "companies all do long-range planning," he said, but "CWA to my knowledge is the first union to do so."

After Toffler and other speakers, some on film, traced the "breakup" of the industrial system that spawned the labor movement, and the "de-massification" of mass production, delegates opened debate on 23 proposals that together are a blueprint for a new union in an age of robots, automation and a changing work force. The proposals were based on 18 months of study by the union's Committee on the Future, headed by the union's president, Glenn Watts.

They range from new efforts to help workers cope with the "de-skilling" of work to the election of a new executive vice president, this time a woman in a union 52 percent female.

But the news was not so much in the specific changes proposed as in the fact that such an effort had been undertaken at all.

Douglas Fraser, outgoing president of the United Auto Workers union, told the delegates in a special audio-visual appearance, "Sure it's hindsight, but if the automobile industry had demonstrated, 10 years ago, the kind of foresight and long-range thinking" that CWA has shown, "we would not be seeing auto workers on the unemployment lines and the bread lines today."

Watts said he is determined to work with management to avoid the mistakes that now haunt workers in autos, steel and other industries.

He disputed charges that unions have become "obsolete or irrelevant" in the modern economy, saying "workers caught up in these massive disruptions need unions more than ever."

The world's largest telecommunications union, CWA represents 675,000 workers in public and private sector jobs, including telephone operators, equipment makers, sound and electronic technicians, and a range of other occupations.

Their industry, while prospering, is caught in one of the fastest riptides of technological change.

The union is trying to educate its own membership to changes at the same time that it is plotting a major bargaining campaign for negotiations with the old "Ma Bell," which is breaking up under court order. The union opened collective bargaining with the American Telephone & Telegraph Co. on May 19.

The proposals on the Committee on the Future envision a highly mobile work force whose members are constantly retrained as technology requires and whose benefits are "portable," following them from one employer to another. The concept of "employment security," it says, should replace the obsolete notion of job security.

This concept will be a key part of the CWA's bargaining with the telephone company, union officials said.

The committee recommends, among other things, that the union "cautiously explore possible new approaches to avoid conflict with employers" and seek to increase the union's voice in employers' response to change.

The committee's report is unusually candid in its public airing of the union's internal difficulties and goals, according to Watts.

Some of the delegates seemed stunned by the array of rhetoric about the proliferation of new technologies, the flight of jobs to foreign countries even in high-tech industries, the influx of women, minorities and immigrants into the job market and the dislocation and displacement of workers in other industries.

Union officials acknowledge that some jobs will be lost forever to machines and that some workers will be dislocated. Their aim, they said, is to ease the change as much as possible, to try to minimize the dehumanizing "de-skilling" of work.

Union member Rosetta Wolfwork has worked for 10 years at a Michigan Bell unit, she said, and has gone from taking consumer calls for repair work to working only with a computer terminal, in what is becoming a paperless office.

She finds it difficult not to have contact with humans but only with a machine. "They tell us, you're making history, but it's like working inside the emergency room of a hospital. I start work at 8, and by 8:15 we're all lined up for Excedrin and Tylenol to calm us down."

Pat Meckle, who has put in over 30 years as an overseas operator in New York City, says she now faces the closing of all long-line international operating centers. "They've only offered typing retraining, and there's a question whether they've got enough typing jobs," she said.

Still, even some of those affected by the changes are leery of changing their union too fast in response.

Marial Rampton, of Salt Lake City, whose job as an account representative for the yellow pages is being done by a machine now, has been downgraded to advertising analyst with an $80-a-month pay cut.

Still, she said, "I think it's a little soon" for the union to make all these changes. "Even management doesn't know everything that's going to happen yet."

Internally, the new proposals call among other things for a stricter accounting of union funds, a reduction in the frequency of conventions and elections, and other measures designed to help pay for the new long-range strategy activities. Programs would have to be justified, rather than being renewed automatically on the basis of tradition.

Another controversial proposal would add a fourth executive vice president --a woman--to the three men in that position.

"We never looked further ahead than the next contract," a union official said. "Unions generally don't tend to plan ahead. Now we're looking to the next contract and beyond, and not just at our own membership but at the whole . . . environment."

The communications workers are no strangers to technological upheaval. In the 1930s, the unions fought the introduction of the dial system in order to save operators' jobs. "Fortunately," Watts said, "We were unsuccessful," because the resulting boom in demand for service created more jobs.