AY also waits if the previous flight is late. (of course this is not 100% sure)
I had AY from TMP to HEL late 30 minutes and the Aeroflot to SVO waited until everybody got in. Might also be that it was last flight to SVO on that day.
Only negative point is that if the connection time is short and previous flight is late, no time for tax/free
edit: connection time was 1 hour, so even with 30 minutes I had enough time