172 days service time in the majors is a “full” season. So, do the math from the season opener on March 31 to last game. Typically, can come up about 10 days or so after opening day and get those 172 days service time. And new cba has some caveats based on rookie of year tallies even if don’t have the 172 days.
Kinda doubt will be a factor for Mervis making the club but who knows.