Research already presented to groups like the Confederation of British Industry, the Consumers' Association and the Guild of Cookery Writers shows Radio 4 loses as many as 620,000 listeners the minute Today finishes.
After The world at One as many as 400,000 listeners turn off and almost half a million disappear when The Archers ends. This means Radio 4's audience declines faster in the mornings than the rest of the country's radio stations. Most other stations see a slow decline from the mornings to the end of the day, but Radio 4's audience falls from a peak of 2.2 million to 500,000 in two hours.
Mr Boyle's research, seen by The Independent, shows half Radio 4's audience listen to other stations more than they listen to Radio 4. Loyalty to programmes is weak - except for news programmes, Radio 4's audience only tunes into the same slots once or twice a week.
Mr Boyle is also concerned that the average age of the station is 53, and of the 8.3 million people who listen in a week only 1.2 million are under 35. He wants to reverse a trend that has seen younger listeners move to Radio 5 Live.
The research also confirms that Radio 4's audience is overwhelmingly English. Only 500,000 of listeners hail from Scotland or Northern Ireland.
The new schedule will be announced next week and then Radio 4 plans a big public-information campaign to go over the head of a press which the corporation sees as hostile to change, and direct to listeners.
Radio 4 will broadcast a special hotline number - like that used to help re-tuning during Test Match Special - so listeners can get details of the schedule before it goes on air in April. It will also advertise the hotline number in the national press.
Mr Boyle will tell the governors he wants to build on what is good about the station and apply a few modern scheduling techniques. Because Today is so successful he will extend it to take in Farming Today and Yesterday in Parliament.
This has attracted the wrath of MPs, but by airing Today in Parliament late at night the BBC is within its charter obligations on covering Parliament and if he is brave Mr Boyle can ignore Speaker Betty Boothroyd's "expression of concern". To stop the switch-off by 620,000 listeners when Today ends, the 9am slot is to be refreshed so that Melvyn Bragg's Start the Week will turn into a celebrity chat show. Midweek may go altogether, and The Moral Maze will be moved to evenings.
Woman's Hour is likely to move to a 10am start to provide the cement in the morning schedule. A mid-morning drama has also been reported.
The consumer-affairs programme You and Yours may be revamped and the unloved Afternoon Shift is likely to go so that PM can move to a 4pm start time. The "more of a good thing" philosophy will be extended to The Archers, which will get another episode on a Saturday and a longer Sunday omnibus edition.
Saturday mornings, are deemed as ripe areas to pick up listeners so Cliff Morgan's Sport of Four may go as will the anomaly of having the dull and worthy Money Box between lighter-weight shows like Loose Ends and the 12.30 comedy games shows like the News Quiz.
For the changes, and against
Alan Coren, humorist:"I identify Radio 4 as a constituency, or a country, more than a radio station."
Janet Suzman, writer and campaigner: "Leave Radio 4 alone. There is nothing quite like that in the whole world. Why make it like the dumbing- down radio stations?"
Steve Barnett, lecturer in media studies:"We must rely on the good judgement and integrity of the controller."
Iris Murdoch, writer: "Keep it old-fashioned ... don't bring it up to date."
Brian Sewell, art critic: "Most of people who listen to Radio 4 are museum pieces. I am a museum piece. It is going to be spoilt if it is changed. Just get rid of the cricket and Kaleidoscope and I'll be content."
Anita Brookner, writer:"I want more seriousness ... more talks, more lectures ... more information basically about the world."
Research by Agnes Severin