SQL Server System Versioned Table Execution Timing

I am trying to learn more about system versioned tables in SQL Server so I am running a script to perform simple DML statements on a system versioned table and capturing different times stamps that are used for inspecting the tables between each statement.

Setup

IF  EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[EXAMPLE_TABLE]') AND type in (N'U'))
ALTER TABLE [dbo].[EXAMPLE_TABLE] SET ( SYSTEM_VERSIONING = OFF  )
GO
DROP TABLE IF EXISTS [dbo].[EXAMPLE_TABLE]
GO
DROP TABLE IF EXISTS [dbo].[EXAMPLE_TABLE_HISTORY]
GO

CREATE TABLE dbo.EXAMPLE_TABLE_HISTORY (
    ID INT NOT NULL,
    -- 'data'
    ColA VARCHAR(255) NULL,
    ColB VARCHAR(255) NULL,
    ColC VARCHAR(255) NULL,
    SysStartTime DATETIME2 NOT NULL,
    SysEndTime DATETIME2 NOT NULL
);
CREATE CLUSTERED INDEX IX_EXAMPLE_TABLE_HISTORY__SysEndTime_SysStartTime
    ON dbo.EXAMPLE_TABLE_HISTORY (SysEndTime ASC, SysStartTime ASC);

CREATE TABLE dbo.EXAMPLE_TABLE (
    ID INT NOT NULL IDENTITY(104729, 1),
    CONSTRAINT PK_EXAMPLE_TABLE
        PRIMARY KEY CLUSTERED (ID),
    -- 'data'
    ColA VARCHAR(255) NULL,
    ColB VARCHAR(255) NULL,
    ColC VARCHAR(255) NULL,
    -- system versioning
    SysStartTime DATETIME2 GENERATED ALWAYS AS ROW START HIDDEN NOT NULL,
    SysEndTime DATETIME2 GENERATED ALWAYS AS ROW END HIDDEN NOT NULL,
    PERIOD FOR SYSTEM_TIME(SysStartTime, SysEndTime)
)
WITH (SYSTEM_VERSIONING = ON (HISTORY_TABLE = dbo.EXAMPLE_TABLE_HISTORY));
GO

Problem

I am running into a strange situation where the results don't appear to be correct unless I add delays into the code. For example, when running the below script I would expect the table to be empty at T0, however it returns data from the first insert.

-- perform simple dml statements
DECLARE @t0 DATETIME2 = SYSUTCDATETIME();
INSERT INTO dbo.EXAMPLE_TABLE (ColA, ColB, ColC) VALUES ('a', NULL, NULL);

DECLARE @t1 DATETIME2 = SYSUTCDATETIME();
UPDATE dbo.EXAMPLE_TABLE SET ColB = 'b' WHERE ColA = 'a';
INSERT INTO dbo.EXAMPLE_TABLE (ColA, ColB, ColC) VALUES ('d', NULL, 'f');

DECLARE @t2 DATETIME2 = SYSUTCDATETIME();
DELETE dbo.EXAMPLE_TABLE WHERE ColA = 'a';

DECLARE @t3 DATETIME2 = SYSUTCDATETIME();

-- inspect tables at specific points in time
SELECT * FROM dbo.EXAMPLE_TABLE FOR SYSTEM_TIME AS OF @t0;
SELECT * FROM dbo.EXAMPLE_TABLE FOR SYSTEM_TIME AS OF @t1;
SELECT * FROM dbo.EXAMPLE_TABLE FOR SYSTEM_TIME AS OF @t2;
SELECT * FROM dbo.EXAMPLE_TABLE FOR SYSTEM_TIME AS OF @t3;
SELECT * FROM dbo.EXAMPLE_TABLE;

'FIX?'

If I add in delays everything seems to work, but I am want to understand if the delays are needed or if they are 'working' accidentaly.

-- perform simple dml statements
DECLARE @t0 DATETIME2 = SYSUTCDATETIME();
WAITFOR DELAY '00:00:00.100';
INSERT INTO dbo.EXAMPLE_TABLE (ColA, ColB, ColC) VALUES ('a', NULL, NULL);

DECLARE @t1 DATETIME2 = SYSUTCDATETIME();
WAITFOR DELAY '00:00:00.100';
UPDATE dbo.EXAMPLE_TABLE SET ColB = 'b' WHERE ColA = 'a';
INSERT INTO dbo.EXAMPLE_TABLE (ColA, ColB, ColC) VALUES ('d', NULL, 'f');

DECLARE @t2 DATETIME2 = SYSUTCDATETIME();
WAITFOR DELAY '00:00:00.100';
DELETE dbo.EXAMPLE_TABLE WHERE ColA = 'a';

DECLARE @t3 DATETIME2 = SYSUTCDATETIME();
WAITFOR DELAY '00:00:00.100';

-- inspect tables at specific points in time
SELECT * FROM dbo.EXAMPLE_TABLE FOR SYSTEM_TIME AS OF @t0;
SELECT * FROM dbo.EXAMPLE_TABLE FOR SYSTEM_TIME AS OF @t1;
SELECT * FROM dbo.EXAMPLE_TABLE FOR SYSTEM_TIME AS OF @t2;
SELECT * FROM dbo.EXAMPLE_TABLE FOR SYSTEM_TIME AS OF @t3;
SELECT * FROM dbo.EXAMPLE_TABLE;

At this point my best guess is SQL Server captures the time at the beginning of the DML statment and there is simply not a long enough delay at the precision of a datetime2 to distinguish between the time captured and the next statement.

Is this assumption correct? Any explanation or documentation would be helpful.

All testing was performed with SQL Server 2017.