I don't think that is the case.
I first stumbled across this in a single-sided document and after giving it another look, it does not seems like it's overlowing in the left margin, the same way it does to the right margin before the split, but rather being centered, overvflowing the same amount on both sides.

You can see this on live.contextgarden.net with the following example:

```
\showframe

\startplacetable[align=left,location={split},title={test}]
\bTABLE[option=stretch,split=yes,textwidth=\dimexpr\textwidth+\rightmarginwidth+\rightmargindistance\relax]
\dorecurse{100}{
      \bTR
        \bTD Cell 1 \eTD
        \bTD Cell 2 \eTD
        \bTD Cell 3 \eTD
      \eTR
    }
\eTABLE
\stopplacetable
```

Niklas

19.11.2024 18:05:00 Duncan Hothersall <dh@capdm.com>:

> If your document is set up as double-sided (\setuplayout[alternative=doublesided] or similar) then I think this is the expected behaviour, since the margins flip on odd and even pages. You could set up as single-sided to prevent this but you may be relying on the double-sided setup for other things (page numbers, headers and footers for example).
> 
> Duncan
> 
> On Tue, 19 Nov 2024 at 15:11, Niklas von Hirschfeld <niklas@vonhirschfeld.eu> wrote:
>> Hi there,
>> 
>> when having an overflowing TABLE in width (e.g. with the TABLE option
>> 'textwidth=\dimexpr\textwidth+\rightmarginwidth\relax') the position
>> (horizontal) changes after a split.
>> 
>> Before the first split the table overflows into the right margin. After
>> that the position changes and it's overflowing into the left margin.
>> 
>> Here is a minimal example:
>> 
>> \startplacetable[location={split}]
>> \bTABLE[option=stretch,split=yes,textwidth=\dimexpr\textwidth+\rightmarginwidth+\rightmargindistance\relax]
>> 
>>   \dorecurse{100}{
>>        \bTR
>>          \bTD Cell 1 \eTD
>>          \bTD Cell 2 \eTD
>>          \bTD Cell 3 \eTD
>>        \eTR
>>      }
>> \eTABLE
>> \stopplacetable
>> 
>> Is this behavior expected?
>> 
>> I would like the position to be the same as before the split,
>> overflowing into the right margin, how could I achieve this.
>> 
>> 
>> Thank you and best regards
>> 
>> Niklas von Hirschfeld
>> 
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