@Piotrd - tends to reduce battery life, as when no bluetooth connection it automatically turns on wifi (you can switch this off); however now that your connection issue is resolved it shouldn’t be a major issue going forward.
PS - would recommend switching play store on watch to manual update - you will get a notification when their is an app to update, and this way it stops the watch choosing an inoportune mate to update (when it might try and use wifi when there isn’t and or end up using bluetooth for download - which can take up quite a bit of juice).