@VayaWillemen
Tracking client version numbers is a fruitless task, best to try and ignore it. Recently there has been a pause in client updates, I've seen devices as far back as 1.3.00.28779 from November that are happily not updating to anything else. If you look in the client logs (right click on the Teams icon in the status tray) they check and are told they are up to date.
There is not significant consistency, versions do not get deployed to everyone at the same time, one machine can be offered an update while another isn't. Sometimes whole versions are skipped for some device and not others. From what I can tell recently users in the same tenant are not offered updates at the same point, a degree of staging is being done by Microsoft where they deploy to something like 10% then 20% and so on.
If you login or are a guest in another tenant the stage may be different, so you might then get a newer version. If you access a tenant where you are in another level of deployment ring (for example Public Preview, a TAP tenant or Microsoft's tenant) you could well get a new version offered.
Ultimately it doesn't matter, the Teams client is kind of like a browser housing a web application, new features, apps etc can be lit up without the client being updated. When a feature does have a dependency on native code in the client Microsoft have deployed that well in advance of the feature being enabled in the web app.
If you want to verify if your client is updating properly perform a check for updates then look in the logs (Teams in Status Area, Right Click, Get Logs). If you see some URLs being mentioned then ultimately a message
<4000> -- info -- App up-to-date
then your client is current.
