Scroll is not smooth if initial items quantity is small

[reeq-dev]

Screen.Recording.2021-05-05.at.18.07.30.mp4

Hi once again, so the second issue is: whenever you have a small initial list like 5-10 items with small height, e.g window height is 896, and the content is about to 800/700 and you try to call onStartReached function scroll position will jump on items append, and later on everything is fine. Also as soon as i increase initial quantity of items to 100 then issue is gone and everything works very smooth. So for my case i tried to increase initial items quantity and set initialScrollIndex with getItemsLayout props, but with such approach it becomes even much worse than it was before

IOS simulator - iPhone 11 - 14.4

"react-native": "0.64.0",
"react-native-bidirectional-infinite-scroll": "^0.3.3",
"@stream-io/flat-list-mvcp": "^0.10.1",
"react": "17.0.1",