I'm sure Apron try their best to confuse controllers and pilots alike. You can be sure that AZA209 will always park on stand 209, and EY303 on 303! S'pose it makes it easier in a way as there's only one number for the pilots to remember (you'd think that was easy wouldn't you
!)
Earlier this week SAS515 was followed in trail by SAS1515 down the approach. This stuff happens all the time.
Cheers!