The 'directions' on polyester resins are 'really' the amount of catalyst needed at ~70°F.

When working with 'polyester' at different ambient temps. you really have to 'sample' / test the amount of catalyst vs. resin to arrive at a realistic pot life and cure time. Just run a few simultaneous small (2oz.) samples in small 'paper drinking cups' with measured but varying amounts of catalyst in each (simply count the number of 'drops' of catalyst added), then mix, and simply observe the time it takes to begin to gel, then 'kick' (initial cure), choose the mix ratio that suits your needs ... at the moment.
15-18 'drops' equals to approx. 1 milliliter (1 cc) of catalyst.

Cold weather will greatly extend the pot life and also extend the cure time and vice versa.

Slow heat soaking will increase the rate to cure time; if it was 'real cold' when you did this, simply wait ....... until APRIL or Summertime for the cure to fully 'kick'.

Heat Lampc., etc. will definitely be your friend at this time.