Returned reference id is different than the id stored in the database (same query)

Hello there, nice people!
I am running the query below.

If I use the first variation of Select (just reading the document I created), the reference ID returned differs from the one stored in the database.

However, the second Select (using a Get before Select) returns the correct ID.

Let(
    {
        doc: Create(Collection('someCollection'), {
            data: {
                studio: CurrentIdentity(),
                field1: '...',
                field2: '...',
            },
        }),
    },
    // The problem  is here
    Select(['ref', 'id'], Var('doc'))  // RETURNS INCORRECT ID
    Select(['ref', 'id'], Get(Select('ref', Var('doc')))) //RETURNS CORRECT ID
)

Does anybody know if this is a known bug?