Odd bug when selecting 32 columns in source query of copy data task

I have been fighting a very odd issue in a pipeline this morning and can reproduce the issue at will.

Imagine a simple pipeline with a copy data task using a SHIR.

For the source query, if I specify 32 columns in the query - it errors with a message that it cannot find the first column in the dataset.. If I specify 31 columns, or 33 columns its fine.. It doesn't matter what order the columns are in, doesn't matter what columns I choose, or the names, or whatever, but the moment I choose 32 columns - It errors with a message that it cannot find the first column (whatever I select as the first column)

Repro - Copy data task, source query = 

SELECT 1 AS col1
	, 2 AS col2
	, 3 AS col3
	, 4 AS col4
	, 5 AS col5
	, 6 AS col6
	, 7 AS col7
	, 8 AS col8
	, 9 AS col9
	, 10 AS col0
	, 11 AS col11
	, 12 AS col12
	, 13 AS col13
	, 14 AS col14
	, 15 AS col15
	, 16 AS col16
	, 17 AS col17
	, 18 AS col18
	, 19 AS col19
	, 20 AS col20
	, 21 AS col21
	, 22 AS col22
	, 23 AS col23
	, 24 AS col24
	, 25 AS col25
	, 26 AS col26
	, 27 AS col27
	, 28 AS col28
	, 29 AS col29
	, 30 AS col30
	, 31 AS col31
	, 32 AS col32

Sink = no mapping, tablename passed in as part of foreach and auto-create table

Error:
Failure happened on 'Sink' side. ErrorCode=UserErrorInvalidColumnMappingColumnNotFound,'Type=Microsoft.DataTransfer.Common.Shared.HybridDeliveryException,Message=Column name 'col1' cannot be found in either source data or column mapping.,Source=Microsoft.DataTransfer.DataContracts,'

But in the example above, if I add a "col33", it works fine