Egyptian ancestry of Palestinian Arabs

Yesterday I had a Palestinian Arab customer (he told me that he is Palestinian after receiving his results), and he scored 20% Egypt (mostly Kafr El Sheikh Governorate). And if I remember correctly, he is not my first Palestinian customer who scores Egypt, but few other Palestinian customers before him also scored significant percentages from Egypt.

What do you think about this? Was there a migration from Northern Egypt to Palestine?

BTW the rest of his results was mostly Lebanon & Palestine, but also 5% Greek Dodecanese.

Question is how much was his Levant ancestry. The Egyptian ancestry to the Southern Levant was 'successive' dating back to the Middle and Late Bronze Age.