Good that you have the motor starting cold easily now , it's still a little strange that it was fine a couple weeks ago.
As we know the hole in the choke butterfly allows a small amount of air to bypass the closed choke plate. This can help stabilize the engine during starting, allowing it to run smoothly before the choke opens fully. It prevents flooding and aids in maintaining combustion until the engine warms up enough to run on a normal mixture.
Some old Briggs have a spring loaded check valve that opens after the engine fires cold to help with the fuel mixture on start up.
As we know if the operator opens the choke straight after starting there won't be a problem.
