He's talking about this https://www.express.co.uk/comment/expresscomment/1357379/us-election-2020-donald-trump-joe-biden-pollster-fail
It was in a british newspaper but Patrick Basham is not british (not based in britain either), nor is he a pollster.
It's a bit confusing but I am sure Trump must have known and is just playing with us by saying things that are wrong.
It's because the absentee ballots take longer to count. They have to be taken out of two envelopes and signatures matched etc, whereas the in-person ones are ready to count.
Did you have sources to send him too? Would love to be able to send people the actual proof rather than just a list of things which could easily be made up.