I feel ive been turned over, yes i agree i should have asked more questions prior, but to be held totally responsible is unfair, i never use mapei, client supplied, always ditra👌, thanks againBut .... to be honest the Tiler should know these. Its the installation date of the screed you need and whether it was exposed to the elements at all after installation , lengthening the drying process. I’ve had some projects where everyone’s lied about timescales 😂.
in future bin the Mapei membrane and use Ditra. Much better for sand/cement screeds which might still be a tad green.