Update, flooring contractor contacted Mapei and had a good chat with their head guy. They ran through the whole procedure, established the correct amount of water was in the mix, 4.2 litres , in fact that's less than I do! It was confirmed a slump test was carried out on the first batch mixed which confirmed it was not too watery or too dry. Ran through everything and it was said the contractor is very thorough in what he does. The Mapei guy asked if there were any kinks in the hoses at any point, a job up in Bradford had the same problem. Turns out there may have been kinks at points , causing the fibres to gather at the kink then spit out intermittently causing the fibrous finish in parts of the floor. It was said that a light brush to remove the top should release any moisture left in the slc which the contractor has done. It was also said the strength of the leveller has not been compromised.
Thank god for that!