Hi Neale. I'm wondering if perhaps the bag you have was produced during the summer and therefore has a higher addition of retarder in the mix. Please could you let me have the batch number and i'll ask the Chemists to take a look at the product tomorrow morning.
I'm surprised by this but lets have a look and then we can go from there.
The adhesive will set and once set the properties of the adhesive will be the same as adhesive that sets as it should around 3 hours.
Please do let me know of any small issues like this, its important to keep on top of things like this.
Cheers
Mark