Here is a link to working example that demonstrates this problem:
http://www.arnaco.com/test/
On the page there are 2 buttons. First loads grid with 500 records, second with only 40. Please use following steps to recreate:
1. Click first “Reload Grid” (top left) button and see grid loads.
2. Scroll grid to Page #20, so it shows records 201 – 240.
3. Click second “Reload Grid With Less Data” button and see grid reloads, but page index is carried over from previouse request.
If you view source of aspx page you will see that onclick I will explicitly set {page: 1} ($('#scrolling').setGridParam({page:1, filter: 1}).trigger('reloadGrid');”).
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