For those who are wondering:
4th stay: checked out 17th March, points posted 18th March. Free Certificated posted on the 18th as well.
8th Stay: checked out 21st march (I know I know, the last 4 stays were a mattress run
), points posted on the 22nd. The certificate was posted on the 8th of April.
Hope this helps someone
..
Good luck.