Hello,Apparently it's also happening for other applications that are starting later during the boot like GDM.
Somebody has reported an issue on IRC where GDM was taking upto 8 minutes to start (dmesg was showing several "random: systemd: uninitialized urandom read (16 bytes read)" during boot)
That problem might impact lot of people I'm afraid. Installing rng-tools5 seems to help in that case.