While that poll may be done correctly it certainly is an outlier. It was in the field from Mar 15-26 which is a really long time to collect a sample of 1000. Anything longer than a week seems weird to me.
Compare the polling done by other organizations
Legir 45-37-9
Main Street 51-37-4
Angus 56-31-5
IPsos 52-35-6
ThinkHQ 49-38-8
Now since the EKOS poll has 11 days in the field only about half of that sample would be after the latest rounds of the other poll so it’s unlikely to be able to pick up recent significant movement. The EKOS poll is also funded by a partisan group and therefore could be more suspect. More than likely the EKOS poll is the outlier rather than the other 5 having a consistent methodology error or a 5 point positive swing for the NDP and 5 point negative swing to the PCs.
Polls referenced from CBCs poll tracker
https://newsinteractives.cbc.ca/elec...acker/alberta/