I just made a little statistic with regard to all stable updates from 2018 until now:
On average, Manjaro Stable is updated every 8.78 days.
The longest times between stable updates have been 35 days (struggles to become Gnome stable in October 2019) and 36 days (which I think was due to the change to the new forum in July 2020)
The last stable update was on June 14th, so 21 days ago.
There has been a 19-day update duration from May 19th to June 7th when you were already using Manjaro.
With all that said … statistically there is nothing to worry about and the next stable update is apparently coming quite soon 