5 fields in a repeater does not sound like a lot. How many rows are being submitted? How many other fields are there?
AJAX would not matter, you still need to deal with the timeout.
I should have asked first, but are you sure it’s timing out and not an error of some kind? I would turn on debugging and error logging and check to make sure there are no errors. There may not be enough fields to cause a timeout.
I actually have a plugin that does what you suggest but it’s not for everyone. But you have to make sure everything is error free before using it.
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