it says like a year, doesn't say "will be a year" which could support the argument in favour of a deceptive effect. the time of dajjal will be of utmost confusion. so because of it feeling like a year due to the amount of things he's achieving in such a small period of time, people could argue over how long his first day actually is. some will say months, some weeks, some a year.... if people know that the time between say zohar and asr feels like it's been elapsed then of course people will calculate the time and hence perform Salah. this will carry on in between the Salah intervals and people will continue to offer Salah whilst the magic is still going on making it feel like time is being stretched. in other words, life goes on as normal for the mu'mins whilst the deceived marvel at the dajjal street magic show... dajjal will want to stretch the time so people delay performing Salah.