UI test first tap after a swipe action fails

I am writing UI tests for our app. The sequence we need to test is:

• user swipes up to scroll the current table
• after the swipe ends, user taps a cell

It seems that the first tap after a swipe action is discarded. What's going on -- is this a bug? Code follows:

A table has 50 rows, each row containing the text "Row <number>", and tapping a row displays an alert.

This test succeeds:

let myTable = app.tables["AccId_MyTable"]
let row = myTable.cells.containing(.staticText, identifier: "Row 10").element

// Row 10 is visible initially
row.tap()

let okbutton = app.buttons["OK"]
XCTAssertTrue(okbutton.exists, "The tap alert never appeared")

okbutton.tap()

This test fails on the okbutton.exists assert:

let myTable = app.tables["AccId_MyTable"]
let row = myTable.cells.containing(.staticText, identifier: "Row 10").element

// Adding this line causes the test to fail
myTable.swipeUp()

// Row 10 is still visible after the swipe up and should be tappable
// But .tap() fails
// Even adding a sleep(10) between .swipeUp() and .tap() doesn't fix it.
row.tap()

let okButton = app.buttons["OK"]
XCTAssertTrue(okButton.exists, "The tap alert never appeared")

okButton.tap()

Footnote:

Another post I found said you don't need to swipe explicitly before tapping table cell. In our case we do need to swipe, because the swipe triggers the fetch of a new page of data, so without the swipe the table will not contain the element we need.