Using a resource pack that changes the model of "overfilled" bundles (using the predicate filled>1.0) no longer works in 21w20a.

{
    "parent": "item/generated",
    "textures": {
        "layer0": "item/bundle"
    },
    "overrides": [
        { "predicate": { "filled": 0.01 }, "model": "item/apple" },
        { "predicate": { "filled": 1.01 }, "model": "item/diamond" }
    ]
}

Reproduce:
1) Create a world in 21w19a and give yourself a filled bundle, and an "overfilled" bundle

/give @s bundle{Items:[{id:'minecraft:stone',Count:1b}]}
/give @s bundle{Items:[{id:'minecraft:stone',Count:65b}]}

2) Enable the attached resource pack
3) Note that the items have unique textures
4) Create a world in 21w20a (or upgrade that world), and the filled and overfilled bundles have the same textures.