Beyoncé is "very pregnant" -- according to a source with eyes on her as she prepares for her Grammys performance -- and the pace onstage will slow dramatically as a result.
Sources connected with the show tell TMZ, Beyoncé is in rehearsals for Sunday's show but the routine is changing constantly and the word is she will not lock the performance in until Saturday night.
There will be an elaborate digital screen onstage, which TMZ was told will create movement that will cover the slower pace onstage.
And there are other tricks ... TMZ was told there will be cameos during Beyoncé's performance.
One source says Beyoncé has made it clear, "She'll be taking it easier than normal."
One thing we know ... the folks producing Coachella will be watching CBS Sunday night, so they can gauge the likelihood of Bey showing up for April's festival.
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