US economy shrank 0.5% in the first quarter, worse than earlier estimates

I'm a bit confused about the bit about the "Imports expanded 37.9%, fastest since 2020, and pushed GDP down by nearly 4.7 percentage points" bit.

Presumably when they calculated GDP previously, they hadn't seen quite as much imports, but had seen higher spending, thus they misattributed some of it to domestic products rather than imports, though I'm a bit confused as to how they underestimated imports given everything is declared. Perhaps some changes in the price index?

Though other articles talk about the expected GDP next quarter being higher because they don't expect a surge of imports to continue, which makes no sense to me unless one assumes spending remains the same with or without imports.

My theory would be that a lot of companies imported a ton in the first quarter knowing that tariffs were coming.